Not sure what I should do

concept

A few days before my EA sole selling rights contract ended

Doozergirl

It is completely incorrect that you cannot accept another offer. You can accept any offer you like at any time up until exchange of contracts.

I haven't quite worked out which agent the 'non-proceedable' offer has come through? This would really affect my answer to you.

safesound

Personally I'd be inclined to let the guy view the house and if he wants to make an offer that betters the existing offer, I'd tell the second EA that the new buyer had viewed with the first EA but had taken his time deciding to make an offer. The only problem I can see is that if the new buyer has also registered with the second EA he may have been sent your details from them too, and the second EA may have a claim on fee's as who's to say which mailing got him interested in your property.

Doozergirl

Reading again, it does sound like the offer comes through your first agent. Either way, I would certainly be happy accepting the viewing and any decent offer that may be forthcoming.

It sounds like your new estate agent has stepped out of the way and isn't marketing at all for you, in which case there's no deep water, your viewing has clearly come through your old agent who has simply pulled their finger out.