Handbook of ROCOR Liturgical Practice:

Do we make the customary prostrations during a Divine Liturgy for a Great Feast, if it falls on a weekday?

In many places prostrations are not done during Liturgies for Feasts, as if they were Sundays. While this is not prescribed in the Holy Canons (as the prohibition for Sundays is, and which in the ROCOR, unlike in some other jurisdictions, is absolute), it is more or less commonplace throughout our Dioceses that on the twelve Great Feasts we do not normally make the customary weekday prostrations (though again, this falls under widespread ‘local custom’ rather than a rule).