diff --git a/Console/RecoRecoCommand.php b/Console/RecoRecoCommand.php
new file mode 100644
index 0000000..e361d4b
--- /dev/null
+++ b/Console/RecoRecoCommand.php
@@ -0,0 +1,32 @@
+<?php
+
+namespace Kanboard\Plugin\RecoReco\Console;
+
+use Kanboard\Console\BaseCommand;
+use Kanboard\Plugin\RecoReco\Model\RecoRecoModel;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+
+/**
+ * CLI entry point for the RecoReco engine. Run by cron (four times a day from v1.0). Can be run by
+ * hand to test: ./cli recoreco:run
+ */
+class RecoRecoCommand extends BaseCommand
+{
+    protected function configure()
+    {
+        $this
+            ->setName('recoreco:run')
+            ->setDescription('Spawn RecoReco calendar-scheduled cards whose occurrence is due');
+    }
+
+    protected function execute(InputInterface $input, OutputInterface $output): int
+    {
+        $model = new RecoRecoModel($this->container);
+        $count = $model->run();
+
+        $output->writeln('RecoReco: spawned '.$count.' card(s).');
+
+        return 0;
+    }
+}
diff --git a/Model/OccurrenceCalculator.php b/Model/OccurrenceCalculator.php
new file mode 100644
index 0000000..8e8fd65
--- /dev/null
+++ b/Model/OccurrenceCalculator.php
@@ -0,0 +1,70 @@
+<?php
+
+namespace Kanboard\Plugin\RecoReco\Model;
+
+/**
+ * Pure calendar math for RecoReco.
+ *
+ * Given an anchor due date (the drift-free pattern: day-of-month + time), a frequency, and the
+ * "last day" flag, it computes occurrence datetimes. It has NO container dependencies, so it is
+ * unit-testable in isolation (see Test/OccurrenceCalculatorTest.php).
+ *
+ * Occurrences are always computed from the anchor's day, never by marching a clamped date forward,
+ * so a "30th" schedule goes 30, 28/29, 30, 30... and never drifts to the 28th.
+ *
+ * v0.3 implements monthly-by-day; the other frequencies arrive in v1.1 (occurrenceFrom returns null
+ * for them until then).
+ */
+class OccurrenceCalculator
+{
+    const MAX_MONTHS = 120;
+
+    /**
+     * The earliest occurrence at/after $reference (when $inclusive) or strictly after it.
+     *
+     * @param  int    $anchor     Unix timestamp: the pattern (day-of-month + time).
+     * @param  string $frequency
+     * @param  bool   $lastDay
+     * @param  int    $reference  Unix timestamp.
+     * @param  bool   $inclusive
+     * @return int|null           Occurrence timestamp, or null if the frequency is not yet supported.
+     */
+    public function occurrenceFrom($anchor, $frequency, $lastDay, $reference, $inclusive = false)
+    {
+        switch ($frequency) {
+            case 'monthly_day':
+                return $this->monthlyByDay((int) $anchor, (bool) $lastDay, (int) $reference, (bool) $inclusive);
+            default:
+                return null;
+        }
+    }
+
+    private function monthlyByDay($anchor, $lastDay, $reference, $inclusive)
+    {
+        $anchorDay = (int) date('j', $anchor);
+        $h = (int) date('G', $anchor);
+        $i = (int) date('i', $anchor);
+        $s = (int) date('s', $anchor);
+
+        $y = (int) date('Y', $reference);
+        $m = (int) date('n', $reference);
+
+        for ($k = 0; $k < self::MAX_MONTHS; $k++) {
+            $lastDom = (int) date('t', mktime(0, 0, 0, $m, 1, $y));
+            $day = $lastDay ? $lastDom : min($anchorDay, $lastDom);
+            $occurrence = mktime($h, $i, $s, $m, $day, $y);
+
+            if ($inclusive ? $occurrence >= $reference : $occurrence > $reference) {
+                return $occurrence;
+            }
+
+            $m++;
+            if ($m > 12) {
+                $m = 1;
+                $y++;
+            }
+        }
+
+        return null;
+    }
+}
diff --git a/Model/RecoRecoModel.php b/Model/RecoRecoModel.php
new file mode 100644
index 0000000..4a60240
--- /dev/null
+++ b/Model/RecoRecoModel.php
@@ -0,0 +1,170 @@
+<?php
+
+namespace Kanboard\Plugin\RecoReco\Model;
+
+use Kanboard\Core\Base;
+use Kanboard\Model\TaskModel;
+
+/**
+ * The RecoReco engine: find enabled templates and spawn their due occurrences.
+ *
+ * Called by the recoreco:run CLI command. v0.3 handles monthly-by-day and fires everything whose
+ * fire time has arrived (fire time = occurrence - days_before); v1.0 adds the 4-window cron horizon.
+ *
+ * Per template: the native-recurrence yield (decision 13), first-run init / manual-edit re-anchor,
+ * then a catch-up loop that duplicates the card into the target column and advances the cursor.
+ */
+class RecoRecoModel extends Base
+{
+    const CATCHUP_CAP = 24;
+
+    private $calc;
+
+    public function run($now = null)
+    {
+        $now = $now ?: time();
+        $spawned = 0;
+
+        $task_ids = $this->db->table('task_has_metadata')
+            ->eq('name', 'recoreco_enabled')
+            ->eq('value', '1')
+            ->findAllByColumn('task_id');
+
+        foreach ($task_ids as $task_id) {
+            $spawned += $this->processTemplate((int) $task_id, $now);
+        }
+
+        return $spawned;
+    }
+
+    public function processTemplate($task_id, $now)
+    {
+        $task = $this->taskFinderModel->getById($task_id);
+
+        if (empty($task)) {
+            return 0;
+        }
+
+        // Native wins: if the card became native-recurring, RecoReco yields (decision 13).
+        if ($task['recurrence_status'] != TaskModel::RECURRING_STATUS_NONE) {
+            $this->taskMetadataModel->save($task_id, array('recoreco_enabled' => 0));
+            $this->logger->info('RecoReco: disabled on task '.$task_id.' (now native-recurring)');
+            return 0;
+        }
+
+        $meta = $this->taskMetadataModel->getAll($task_id);
+        $frequency = isset($meta['recoreco_frequency']) ? $meta['recoreco_frequency'] : '';
+
+        // v0.3 handles monthly-by-day only; the rest arrive in v1.1.
+        if ($frequency !== 'monthly_day') {
+            return 0;
+        }
+
+        $anchor = isset($meta['recoreco_anchor']) ? (int) $meta['recoreco_anchor'] : 0;
+
+        if ($anchor <= 0) {
+            return 0;
+        }
+
+        $lastDay = isset($meta['recoreco_last_day']) && $meta['recoreco_last_day'] == 1;
+        $daysBefore = isset($meta['recoreco_days_before']) ? (int) $meta['recoreco_days_before'] : 0;
+        $targetColumn = isset($meta['recoreco_target_column']) ? (int) $meta['recoreco_target_column'] : (int) $task['column_id'];
+
+        $cursor = (int) $task['date_due'];
+        $synced = isset($meta['recoreco_synced_due']) ? (int) $meta['recoreco_synced_due'] : null;
+
+        if ($synced === null) {
+            // First run after enabling: place the cursor on the first occurrence.
+            $cursor = $this->firstCursor($anchor, $frequency, $lastDay, $now);
+            $this->setDue($task_id, $cursor);
+        } elseif ($cursor !== $synced) {
+            // The user hand-edited the due date -> re-anchor to it (a reschedule).
+            $anchor = $cursor;
+            $this->taskMetadataModel->save($task_id, array('recoreco_anchor' => $anchor));
+            $this->setDue($task_id, $cursor);
+        }
+
+        // Fire every occurrence whose fire time has arrived, advancing the cursor each time.
+        $spawned = 0;
+        $fireTime = $cursor - $daysBefore * 86400;
+
+        while ($fireTime <= $now && $spawned < self::CATCHUP_CAP) {
+            $this->spawn($task, $targetColumn);
+
+            $next = $this->calculator()->occurrenceFrom($anchor, $frequency, $lastDay, $cursor, false);
+
+            if ($next === null || $next <= $cursor) {
+                break;
+            }
+
+            $cursor = $next;
+            $this->setDue($task_id, $cursor);
+            $fireTime = $cursor - $daysBefore * 86400;
+            $spawned++;
+        }
+
+        return $spawned;
+    }
+
+    /**
+     * The first occurrence: respect an explicitly future anchor (the due date the user set) as the
+     * first one; otherwise jump to the next occurrence on/after now.
+     */
+    private function firstCursor($anchor, $frequency, $lastDay, $now)
+    {
+        if ($anchor >= $now) {
+            return $anchor;
+        }
+
+        return $this->calculator()->occurrenceFrom($anchor, $frequency, $lastDay, $now, true);
+    }
+
+    private function setDue($task_id, $cursor)
+    {
+        // Advance the template's due date directly (no task events) + mirror it for edit detection.
+        $this->db->table(TaskModel::TABLE)->eq('id', $task_id)->update(array('date_due' => $cursor));
+        $this->taskMetadataModel->save($task_id, array('recoreco_synced_due' => $cursor));
+    }
+
+    private function spawn(array $template, $targetColumn)
+    {
+        // The template's date_due is already the occurrence (setDue), so duplicate() copies it onto
+        // the clone. duplicate() copies fields + tags + links + subtasks, but NO metadata, so the
+        // clone is not a template.
+        $newId = $this->taskDuplicationModel->duplicate($template['id']);
+
+        if ($newId === false) {
+            $this->logger->error('RecoReco: duplicate failed for task '.$template['id']);
+            return false;
+        }
+
+        // duplicate() lands the clone in the source column; move it to the chosen target (top).
+        if ($targetColumn > 0 && $targetColumn != $template['column_id']) {
+            $this->taskPositionModel->movePosition($template['project_id'], $newId, $targetColumn, 1, $template['swimlane_id']);
+        }
+
+        // Reset the "[DUPLICATE]" prefix back to the source title (no events).
+        $this->taskModificationModel->update(array('id' => $newId, 'title' => $template['title']), false);
+
+        // Mark the clone: white icon + cannot itself be made recurring; record its source template.
+        $this->taskMetadataModel->save($newId, array(
+            'recoreco_clone' => 1,
+            'recoreco_source' => $template['id'],
+        ));
+
+        // Signal FinanceBuddy (advance the installment). Harmless no-op if nothing listens.
+        $payload = array('source_task_id' => (int) $template['id'], 'new_task_id' => (int) $newId);
+        $this->hook->reference('recoreco:task:spawned', $payload);
+
+        return $newId;
+    }
+
+    private function calculator()
+    {
+        if ($this->calc === null) {
+            $this->calc = new OccurrenceCalculator();
+        }
+
+        return $this->calc;
+    }
+}
diff --git a/Plugin.php b/Plugin.php
index ff4ecd7..e650928 100644
--- a/Plugin.php
+++ b/Plugin.php
@@ -11,6 +11,12 @@ class Plugin extends Base
         // "Recurring schedule" entry in the task Actions sidebar, right after the basic actions
         // (next to native "Edit recurrence"). Opens the RecoReco config modal.
         $this->template->hook->attach('template:task:sidebar:after-basic-actions', 'recoReco:task/sidebar_action');
+
+        // The scheduling engine runs from the CLI (cron). Registered CLI-only so web requests do
+        // not build the console app.
+        if (php_sapi_name() === 'cli') {
+            $this->container['cli']->add(new \Kanboard\Plugin\RecoReco\Console\RecoRecoCommand($this->container));
+        }
     }
 
     public function getPluginName()
@@ -30,7 +36,7 @@ class Plugin extends Base
 
     public function getPluginVersion()
     {
-        return '0.2.1';
+        return '0.3.0';
     }
 
     public function getPluginHomepage()
diff --git a/Test/OccurrenceCalculatorTest.php b/Test/OccurrenceCalculatorTest.php
new file mode 100644
index 0000000..61e6675
--- /dev/null
+++ b/Test/OccurrenceCalculatorTest.php
@@ -0,0 +1,103 @@
+<?php
+
+/*
+ * Standalone test for the RecoReco date math -- no Kanboard / PHPUnit harness needed.
+ * Run with:  php Test/OccurrenceCalculatorTest.php
+ *
+ * OccurrenceCalculator is pure, so this exercises the highest-risk correctness surface (month
+ * lengths, leap years, the last-day rule, the drift-free clamp).
+ */
+
+require __DIR__.'/../Model/OccurrenceCalculator.php';
+
+use Kanboard\Plugin\RecoReco\Model\OccurrenceCalculator;
+
+date_default_timezone_set('UTC');
+
+$calc = new OccurrenceCalculator();
+$failures = 0;
+
+function ts($str)
+{
+    return strtotime($str.' UTC');
+}
+
+function check($label, $got, $expected, &$failures)
+{
+    $ok = $got === $expected;
+    $g = $got === null ? 'null' : date('Y-m-d H:i', $got);
+    $e = $expected === null ? 'null' : date('Y-m-d H:i', $expected);
+    echo ($ok ? 'PASS' : 'FAIL').'  '.$label.'  got='.$g.'  expected='.$e."\n";
+    if (! $ok) {
+        $failures++;
+    }
+}
+
+// 1. Plain day-of-month: the 15th, every month.
+check(
+    'monthly 15th, next after Jan 20',
+    $calc->occurrenceFrom(ts('2023-01-15 10:30'), 'monthly_day', false, ts('2023-01-20 00:00'), false),
+    ts('2023-02-15 10:30'),
+    $failures
+);
+
+// 2. Drift-free clamp: the 30th -> Feb clamps to 28 -> back to 30 in March (NOT 28).
+check(
+    '30th -> Feb (non-leap) clamps to 28',
+    $calc->occurrenceFrom(ts('2023-01-30 09:00'), 'monthly_day', false, ts('2023-01-30 09:00'), false),
+    ts('2023-02-28 09:00'),
+    $failures
+);
+check(
+    '30th -> March returns to 30 (no drift)',
+    $calc->occurrenceFrom(ts('2023-01-30 09:00'), 'monthly_day', false, ts('2023-02-28 09:00'), false),
+    ts('2023-03-30 09:00'),
+    $failures
+);
+
+// 3. Last-day rule: last day of each month.
+check(
+    'last-day: Jan 31 -> Feb 28 (non-leap)',
+    $calc->occurrenceFrom(ts('2023-01-31 08:00'), 'monthly_day', true, ts('2023-01-31 08:00'), false),
+    ts('2023-02-28 08:00'),
+    $failures
+);
+check(
+    'last-day: Feb -> March 31',
+    $calc->occurrenceFrom(ts('2023-01-31 08:00'), 'monthly_day', true, ts('2023-02-28 08:00'), false),
+    ts('2023-03-31 08:00'),
+    $failures
+);
+
+// 4. Leap year: last day of Feb 2024 is the 29th.
+check(
+    'last-day: Feb 2024 -> 29th (leap)',
+    $calc->occurrenceFrom(ts('2024-01-31 08:00'), 'monthly_day', true, ts('2024-02-01 00:00'), false),
+    ts('2024-02-29 08:00'),
+    $failures
+);
+
+// 5. Inclusive vs exclusive at an exact occurrence.
+check(
+    'inclusive returns the same instant',
+    $calc->occurrenceFrom(ts('2023-03-10 12:00'), 'monthly_day', false, ts('2023-03-10 12:00'), true),
+    ts('2023-03-10 12:00'),
+    $failures
+);
+check(
+    'exclusive skips to next month',
+    $calc->occurrenceFrom(ts('2023-03-10 12:00'), 'monthly_day', false, ts('2023-03-10 12:00'), false),
+    ts('2023-04-10 12:00'),
+    $failures
+);
+
+// 6. Unsupported frequency (until v1.1) returns null.
+check(
+    'weekly not supported yet -> null',
+    $calc->occurrenceFrom(ts('2023-03-10 12:00'), 'weekly', false, ts('2023-03-10 12:00'), false),
+    null,
+    $failures
+);
+
+echo "\n".($failures === 0 ? 'ALL PASSED' : $failures.' FAILURE(S)')."\n";
+exit($failures === 0 ? 0 : 1);
diff --git a/VERSION b/VERSION
index 4c06819..09fa2f0 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-RecoReco v0.2.1
+RecoReco v0.3