Following a recent rescan, BBC ONE has become BBC ONE W Mid invalidating all my recurring recordings. Can I just rename it in the Channel table to resume normal working?
You can rename a channel but double clicking on it in the Settings->Channels screen.
That said, recurring recordings etc don't depend on the channel name, so it probably wont help you. They instead refer to the channel ID. If you deleted your old channel and rescanned, the recurring recordings are probably referring to a channel ID that no longer exists, in which case you'll need to recreate your recurring recordings.