Unfortunately, it isn't just BA here in the UK.
I had an horrendous experience last September going on holiday from a regional airport in the UK.
Without going into too much detail, I have a chronic incurable disease, and I am on a lot of prescribed medication from pain management. Because of it, I NEVER put any of my drugs in my luggage which is going in the hold. If I were to lose my luggage, it would be fatal. as most of the drugs I take are only hospital or hospice issued.
As it was only a couple of weeks after the liquid scare incident, I decided to tell the customs staff about them. I also have other equipment, which is life saving and that also was in hand luggage.
After ringing the airport prior to going about their policies, I was told due to medical circumstances, no problem.
When we checked in, we had to have a hand luggage weighed, which had coats in folded up, we would normally be wearing, and we were charged £65.00 excess baggage.
If that wasn't enough I was totally humiliated by the security staff, who emptied the entire contents of my hand luggage onto the counter, for all to see. It was all additional stress I could really have done without.
To cut a long story short, they refused to let me take my hand luggage onto the plane. They sent us all the way back down to check it back in again. I then spent the whole of the flight wondering whether I would see that bag again, as it had gone on so late. They had told us not to go back and wait in the line, go straight to the front, as the flight was waiting to board. They wouldn't let us back to the front, and we had to go through the whole thing again, and be searched again, because we had gone out of the security section, even though it was via a staff door.
I was going to complain, but I don't want anyone putting any note on any related information against my passport. (I don't know if such things happen).
If I was a criminal, smuggling drugs in, I would be taken into a private room, and treated with some dignity, instead I felt totally humiliated.
I personally hate London airports, and all the guys I worked with in the 90's who travelled from the US via London, all complained about immigration being there.
Also, just one other point, some airports have made a type of mock up, which you try to put your hand luggage in to make sure it fits. It is out of some cheap crate, but still if the bag doesn't fit. You guessed it, you can't take it. Only problem is, security who are refusing the bag, and check in who say fine ~ no problem you can take it through, do not communicate with each other. Check in, just want to get you thru, if security then send you back, and they were sending almost everyone back.
Even though my hand luggage, was specifically made for hand luggage several years ago, has never been an issue. Now, it won't fit. So, it looks like they have changed the goalposts. Also, there is a weight limit on hand luggage. The bag has been round the world without a problem up until now.
So, just be prepared and dont put anything in your hand luggage which you may be wanting to keep as discreet.