Holiday and maternity leave
A. All benefits that are linked to length of employment (for example, pensionable service) continue to accrue during maternity leave. So your member will carry on accruing annual leave during her absence from work on maternity leave. And this applies not just to her statutory holiday, but also to her contractual holiday entitlement.
As to when your member can take her annual leave, the decided cases seem to suggest that she cannot simultaneously take maternity leave and annual leave.
However, the key cases on this type of issue, mostly relate to sick leave, so the situation isn’t entirely clear.
Leave must, except in exceptional circumstances, generally be taken in the year in which it is accrued.
So carrying over leave into the following year, after the end of maternity leave, may be problematic.
Therefore, to avoid having to negotiate with the employer over this, it may be prudent to encourage your member to take the appropriate portion of the leave, before she goes off on maternity leave. (The appropriate portion of leave will be the portion of leave that she will accrue for the year during her time on maternity leave).