I've got a 2009 focus 1.6 s petrol, when I go from 50_ 65 mph, the car gets a loud drone

noise, thought it was a wheel bearing, but it doesn't change noise when turning from left to right,. when I drop the revs, the noise stays, but only at 50_65 mph?

It does sound like the wheel bearings to me as I had exactly the same problem with my old Ford Sierra many years ago. Once I reached about 50 to 60 mph, irrespective of engine revs, the droning noise was there. A trip to the garage sorted it out and the noise disappeared.

Certainly sounds like a dodgy wheel bearing.

Usually its the tapered bearing which will increase/decrease when cornering, this day and age the common mono block wheel bearing doesn't do it as much, simply jack each wheel up spin and hopefully you will hear a roughness in one of them.

I will add many years ago there was a TSB regarding the removal of the rear drums, it was ish like this :

to remove the rear drum when servicing the rear brakes undo the 4 retaining bolts that holds the stub to the axle, premature failure "could" happen to the bearing if removed,

IF you do remove the big centre nut a new nut MUST be used ....