I've now read the site, and we're not talking pub bookings, but a church. The same system applies, In my local church, we have Sung Eucharist on the first, third and fourth Sudays of each month. The Second Sunday is our 'Family' service, which includes the youth movements in our area.
On those occasions when a fifth Sunday occurs we have 'Mattins' (Morning Prayer) which otherwise no longer gets a Sunday celebration locally.

Nigel