Turkey cooking instructions-AIBU?

[MichaelBuble]

My first ever AIBU (bit scared)
So my Christmas Day turkey was an overcooked dry disaster. The cooking instructions on the front of the packaging stated 4hrs45 mins, after 3hrs30 I realised it was looking very very well done and googled the cooking time for the weight- should've been more like 2.5hrs!
I'm a very amateur cook and I'm sure a more experienced one would've clocked on sooner. But AIBU to be annoyed with Waitrose for overstating the cooking time by more than 2 hours?
I basted and put bacon on the breast etc. And it was £60! I know it's a first world problem etc etc but it did ruin our xmas dinner and has put me off attempting it ever again!

You should always use foil with turkey, the steam stops it from drying out, and then just uncover for the last half hour - 40 mins of cooking.

I cook mine upside down, then put it the right way up, for the last thirty minutes.

Don't worry. Cooking Christmas dinner is a massive undertaking. Well done for giving it a go! At least you'll know better for next year. Better to over cook it than under cook it and make everyone ill! I had a 5kg turkey, covered in foil and cooked it for 4 hours, taking the foil off for the last half hour. Cooked at 200 for the first half hour, and 150 for the rest. It was perfect - just put about 500mls of gravey in the roasting tin to stop it drying out.