I went through at lunchtime last Weds and it was fine. I have had one flight this year where it was a bit longer / more chaotic and that maybe took 20-25 mins longer than usual.

The queue last week looked a bit long as I rocked up but it moved reasonably quickly.

Don't know what they changed if anything.

However I always allow a decent chunk of time at Barajas as 1) It's simply an enormous airport for the amount of traffic it serves (and BA gates are often a hike) and 2) If I do get through quicker than expected the lounges are actually decent spots in which to work so I usually get a bit done.