Sorry its long but its an effort to give a clear picture…
I have been a tenant for over 10 yrs. Finally managed to buy.
Over the years LL has come if called out for something or another but would go for months without coming because they did not need to.
We looked after the property to the best of our ability, had a window cleaner, regular gardening, all bills and rent paid on time. Never missed a payment or asked for rent relief. Recently had driveway washed.
Before Covid 19, we had a regular cleaner. So the place was generally well looked after.
When we moved in, there was new wallpaper in the bathroom. Come winter, it turned out it was a mouldy spot that started to grow back. We removed wall paper and painted it with ant mould paint.. it became easier to maintain during winter months.
There was some wear and tear, having had to bring up 2 kids during that time. But LL was aware of them.
LL had always wanted to do the kitchen so problems in the kitchen were met with, ‘we plan to extend the kitchen anyway’
The boiler was replaced but the pipes were left exposed and we were left to live with that for a few years. We never complained.
Fast forward two months ago, we completed and exchanged. The day after we collected the keys, we gave a month’s notice to LL. up to this point, I thought we had a civil business relationship.
Few days after notice was sent, we got what I thought was a hostile email from LL complaining that we blindsided them. Notice was not sufficient… contract says one month’s notice. LL listed how they have been lenient over the years, not increasing rent but we return that by not being grateful. They demanded a spot check of the property within ASAP which we couldn’t do due to work commitments, but offered a day we could do.
LL said wants property the way it was when it was handed over to us… well not possible as its been lived in so general wear and tear is expected. Having said that, I expected them to be pleased because of the effort we have made over the years 
Now LL is saying umpteen years ago when we moved in, we moved in 12 days early (I cant even remember). So they are saying our notice should be 12 days less and they set a date. No complaints, we are working towards leaving.
My AIBU is: Are we within our right to call LL on this because as its never been an issue before.
LL is blaming us for property not being maintained outside… I say outside is LL’s responsibility to paint and decorate, Is this U?
LL said they will get a quote for carpet cleaning and fixing things they knew about and send us the bill? I think LL does not want to give us our deposit… AIBU?