That's right
@deptfordmarmoset
I haven't been out with them for a while mind, but I'm still a member. They have 3-5 groups out on a Saturday morning and they cater for a wide range of abilities, I was very welcome in the bottom group with my cronky old hybrid when I first started and it was the same as I worked up to the second fastest group when I got a road bike.
Info here
http://www.teamsidcupcycles.btck.co.uk/. If you turn up say 15-20 minutes before the first ride goes out and introduce yourself then you can get to know a couple of people before the ride starts and they'll point you towards the right group for you, you can also pop into the shop they meet at during normal opening hours and inquire there. Some rides have a coffee stop, but there's coffee and a cake at the shop after the ride.