On a similar note – I unblocked the fire place in the kitchen of our Victorian house.
It was just plasterboarded over so didn;t take long and virtually no mess.
Then I spotted the old register plate blocking the chimney. Decided to tap it with a hammer.
It collapsed, bringing down the 6 inches of soot that was sat on top of it. I looked like a Laurel and Hardy ‘after’ shot and the kitchen and hall weren’t in much better shape. Took me more than a day to clean everything up – soot gets everywhere.
In the OP’s case – wait until 8pm on Christmas eve in case there’s some unavoidable DIY catastrophe you’ll trigger. We’ll enjoy reading about your Christmas 😉