IF: How long can the start of an IF project be postponed?

There are 3 such options:
1. The first day of the month after the entry into force of the grant agreement
2. A fixed starting date
3.  The effective starting date to be notified by the beneficiary, which must be within 12 months from the date the Agreement enters into forceIn the first two cases the start date is clearly stated, and no further action is required from the beneficiary (project starts at the said date).
In the last case, however, although an indicative start date was asked during the GA preparation, the start date of the action only becomes effective once the PCoCo (supervisor) or the PLSIGN notifies the Project Officer of this date (by sending a Formal Notification via the PPGMS – Participant Portal Grant Management System), hence the reminders sent when the indicative date approaches (pre-financing is triggered 10 days before the effective start date).