The UK is confusing as there are lots of local restrictions in place so it depends on where you are. Things are beginning to spike again but no total lockdown anywhere as far as I know.
As for Cos, I bought this dark blue hoody which was probably the least interesting thing in the shop, but I'm wearing it today with some Margaret Howell narrow leg wool trousers and it dresses them down just as I'd hoped. It says it's cropped but it isn't - it just doesn't end smack in the fattest part of my thighs like a lot of hoodies and sweats do.
I am delighted to see tank tops are back, e.g. here and here and here. My favourite doesn't seem to be online yet but it was in grey wool with a deep V-neck and a very sharp, Margaret Howell-esqe vibe. If it hadn't been grey I'd have struggled to resist but I've vowed to lay off that colour for now.
(By the way, Cos, please call them by their correct name - a vest is what your mum makes you wear when it's cold.)
Then they had some wide leg grey flannel trousers - not a lot of use in my current life but still delicious. I think these might be the ones but I'm not sure as they looked full length in real life.
A few interesting pleated things
And I liked some of the flat shoes too e.g. these and these Am I getting bored with brogues? 
If trying on had been allowed my credit card might have got hammered but as it was, I looked, admired, paid for the hoody and walked away 
I then went looking for dark blue, cotton, logo free joggers - not to wear with the hoody but to tone down blazers. But the best I found were in M&S and they didn't have my size. They're all sold out on the website too, so that will have to wait.