You are a few miles south of me and there should be abundant Ivy down the Vale for them. I would hold back on feeding for a couple of weeks and keep a check on their weight, you want laying space for your queen as well. See what happens with the weather after this wet spell, if we get some half decent days, they will be out in droves. Do a final assessment and feed any who need topping up.
As a guide I've recently fed all of mine, they get four pints of invert, then a couple of days later a further four pints with thymol added. That was nearly a week ago.
It can't get much worse than last year when we had constant rain from September to March and no colony had more than twelve pints in total.
If when hefting you conclude that the hive would be difficult to pick up and you wouldn't fancy carrying it very far, they should be fine.
Is this your first season? How has it been?