Due to be served section 21. Advice please

FlorayG

You need discussion with your landlord, in writing, if you want to leave the house less than spotless ( which I think is reasonable considering she's going to gut it)
Some landlords are money grabbers and might take pictures of the state of things, claim against your deposit and next day rip it all out. It's going to depend what sort your is as to how carefully you need to proceed
Are you planning to comply and move out on the proposed date? If so then your landlord should be very pleased to return your full deposit no questions 

propertyrental

FlorayG said:

....
Some landlords are money grabbers and might take pictures of the state of things, claim against your deposit and next day rip it all out. It's going to depend what sort your is as to how carefully you need to proceed.....

Just to play devil's advocate - the LL is legally perfectly entitled to do this. Indeed if the T has caused damage etc, then of course the T has a liability.

No different to a car claim; if you scratch my car I can claim £100 (whatever) for the scratch, but whether I decide to get the scratch fixed, or drive around in a scratched car (spending the £100 at the pub) or sell the car, is entirely my choice.

So don't scratch my car and don't damage my house.