What track bike (for the track)?

I asked a few weeks back about winter training, and was told that the Saturday intermediate sessions will continue but only for those with their own bikes. Hopefully I'm not misinformed.

The calendar on their web site shows the intermediate sessions running through the winter from 1100-1230
http://www.hernehillvelodrome.com/calendar/

That said they are planning to put up lights, install a new hard standing and 250 metre track in the infield too this winter. That might get in the way.