Associate
I'd say you'd be ok with what you've got. I'm guessing the solicitors are working from home or whatever, plus (assuming) its a residential mortgage offer, they are regulated and a lender shouldn't be able with withdraw that, well, under normal circumstances.
I'd say you'd be ok though.
In worst case I doubt you'll have problems in the future doing a rate switch with your current lender they probably won't do a valuation, just an AVM or not even bother at all, given they will already have a valuation of your property on file, more so the lower the loan to value.
Cheers BUDFORCE. Yes it is a residential mortgage, new mortgage offer was valued using AVM already, but current lender i believe is using value we purchased at (doesn't effect the mortgage rate they can offer even with the 30k price difference in valuations based on bought price 2 years ago vs current AVM).
Even if we end up on the banks 4% default rate as mortgage is delayed slightly, the extra paid for that month is still less then paying an upfront fee.