As of 5ff92ecc months October, November and December are no longer
represented as 'a', 'b', 'c', but in their numerical forms.

Unfortunately due to massive code duplications there are a few places
that was not changed at the same time.  Fix the left over instances.

Ticket: #7175
(cherry picked from commit 4322139101ec95cc4bffcc32d2067c2538ac7d12)