Since everyone is voting I want to be part of the fun too! One thing to note is that hotel prices still have plenty of time to change in either direction.

My top choice would probably be arriving the day before and night in central London or indeed near Heathrow if the price different is huge ,but for now I'd book whatever is best and flexible and keep checking. Black Friday and Cybermonday round the corner, January sales, chances are that the cheapest hotel prices will come up later rather than now.

Plan B for me would be train in the morning. I know it sounds like a pain (train, then tube, then Elizabeth line or Heathrow express ifyou must) compared to flying, but there are many more trains than plane and whilst the plane is 95% certain to be fine, if there is a major issue of sorts, then domestic flights in general and MAN in particular tend to be the first sacrificed and of course if this happens, the trains will be overbooked so chances of making the train last minute will be limited and expensive. There may even be coaches which would probably be safest of all and probably some straight to Heathrow.

Option 3 flight in the morning and hope for the best.