on Google Cloud Platform Cloud SQL pg_cron is not working on monthly and weekly schedule

I installed pg_cron extension (v.1.4 ) on GCP Cloud SQL PostgreSQL (v.14) .

I instaleld it on "postgres" database and it works smoothly on daily schedule

E.G.

```
SELECT cron.schedule('test cron OK', '21 18 * * *', 'VACUUM (FULL, VERBOSE) cron.job');
SELECT cron.schedule('test cron OK', '21 * * * *', 'VACUUM (FULL, VERBOSE) cron.job');
```

But when I schedule on monthly or weekly bases the job will not run (I can't find any attempt logged in cron.job_run_details or errors in database logs ) : E.G.

```
SELECT cron.schedule('test cron KO', '49 19 * * 4', 'VACUUM (FULL, VERBOSE) cron.job');
SELECT cron.schedule('test cron KO', '21 18 5 * *', 'VACUUM (FULL, VERBOSE) cron.job');
```

Do you have any idea what is the reason of this behaviour ?

Thank you,

Paolo

Start by reproducing the weekly and monthly cron.schedule examples from the issue on PostgreSQL 14 with pg_cron 1.4, comparing them with the working daily schedules. Inspect cron.job and cron.job_run_details, and check database logs for scheduling attempts. Done means identifying whether the behavior is a pg_cron defect, a PostgreSQL schedule interpretation, or a Google Cloud SQL limitation, then documenting the supported behavior or required change.

Written by the indexing model from the issue text.