These easy brake adjustment won't be quite so easy if the adjusters are seized. It can happen if not done for a while, judging by your handbrake that could have been a while
I'd get that sorted pronto, many years ago a good friend of ours put her two young daughters in the car shut the door and it started to roll backwards. Out of the drive, over the pavement, large road, grassy bank, through a wooden fence into an office carpark, before hitting a metal bollard and stopping. Much panic all around, the girls were fine, the car, fence and bollard not. Twenty years on, the different coloured wooden fence panel across the road serves as a daily reminder.
Mine are done every year and I always need a hammer and drift to convince one of the star adjusters to play .... and that's after replacing adjusters and putting a bit of copper grease on threads ... definitely easier to have taken drums off before starting procedure.
There are reports of an unmanned (unfemaled?) white bus just rolling past Newbury heading down the A34