So I've just collected the multi entry visa.
On the whole the process was really smooth.
Booking an appointment via their website was super easy. Although when I booked there was about a 2-3 week lead time for the next available appointment, so you need to allow plenty of time for this.
Having a pre-booked appointment is much better as there was no queue whatsoever when it came to dropping off my application form and documents.
The security guard lets you in and you sign into the arrivals book. A couple of minutes later they call you into the office to hand over your documents and pay for the visa.
The only difference I noticed from doing this pre covid was the consular staff spent ages studying my bank statement. The guidance on their site is quite vague around having adequate funds, so I always take a bank statement just in case. There was about £45k in the account and he stared at it for a long time and asked what currency this was in. Whether or not this means they're now checking funds a bit more thoroughly or just that I'd given him a document he didn't really need, I'm not so sure. However, it's certainly worth having some proof of funds with you just in case it's needed.
I was in and out in about 10 minutes.
Passport is ready for collection the following working day from 1.30 to 3pm. They give you a receipt when you drop off the documents which you need to show to collect the passport.