This estate agent is not to be trusted.
It was clear that the agents conspired to increase my offer on the grounds of being gazumped by a fictional party. This was put into effect by initially not issuing a bill of acceptance of the offer price, followed by not updating RightMove as to the status of the property being "sold stc" for more than week.
If your offer has "been accepted" but details are "it is in the post" and the website will "update in 24 hours" for a few days, await the next step: a mystery buyer will suddenly pipe-up, hailing from a country known for its monetary excess, putting in a cash offer - coincidentally - moments after your survey is confirmed. And then, you will receive outpourings from Ocean of how "we told the vendor that you are the more reliable buyer, but he insisted on you bettering this new bid", plus other flattery.
And don\'t believe a word of it. Call their bluff, because that is what they are doing.