Congratulations @readytosell! Seconding all the jealous people 
@blacklilypad I'm sorry, I can't imagine living with my in-laws, we'd just clash over everything. They did suggest it a few weeks ago (although it's our buyer who is the issue, so it didn't really help).
@Getyourarseofffthequattro I wonder if they're not getting a response from your seller? It turns out that that's why the EA was being arsey with us... they weren't getting updates from our buyer.
We got bad news yesterday. Our vendor is remarketing and has viewings today. They don't feel our buyer is proceedable, and while the vendor really wants to sell to us and feels bad on a personal level, he has to look after his own interests. They were baffled as to why our EA hadn't suggested remarketing weeks ago.
Talked to our EA. Our buyer hasn't been very communicative with them but they say they had no reason to believe that he wouldn't be making progress... now it's clear that he hasn't. He hasn't got a deposit, and he'll need to pull out if the appeal isn't successful. Apparently they did consider advising us to remarket, but thought it'd be "harsh" on our buyer.
We've gone back to the other person who made an offer who is thinking it over, and will let us know tomorrow... but I'm not confident.