During the probationary period, the notice period starts to run on the day of notification (and thus of dispatch) of the resignation letter.
The period of notice is calculated in calendar days and not working days.
The notice period must end no later than the last day of the probation. In no circumstances may it extend beyond the end of the probation, otherwise the contract may be reclassified as a definitive contract.
In fact, where the probationary contract is not terminated before the expiry of the probationary period agreed by the parties, the employment contract is regarded as having been concluded for the period agreed in the contract as from the day of entry into service.
Example
A contract of indeterminate duration provides for a probationary period of 6 months from 15 January to 14 July. The notice period to be observed in the event of resignation is 24 days. The contract must be terminated no later than 21 June (14 July – 24 days).
If termination takes place after 21 June, the notice period will exceed the probationary period and the contract will then be deemed to be of indeterminate duration and the notice period of one month corresponding to definitive contracts will have to be observed.