Lunchtime sessions would be fine. They used to run in the Phoenix from around 12 -3pm on Sat and Sunday, sometimes they went on longer.

The main problem with that was that the space was a bit limited if there was a big crowd. There were some very good evening sessions too, especially when Trommelflut (spelling?) were around.

It's only in the last couple of years that the only singing sessions that I've found (Synbyn at the Vaults excepted) have been at the Crown and Anchor; and, for very good reasons, they don't start until quite late.