UPDATE 11:20 GMT: Spreedly back now.
The payment processor who handle KeepMeBooked subscriptions, Spreedly, seems to be down.
This means you can't amend your KeepMeBooked subscription or sign up for a free trial right now
(It doesn't affect anything else: KeepMeBooked itself is fully available, and of course your own payments from guests are completely unaffected. You just can't amend your KeepMeBooked subscription or sign up for a new free trial just now.).
We are awaiting response from Spreedly regarding when they expect this to be resolved and we'll update here.