I posted on here recently, I flew from LGW about 5-6 weeks ago in the middle of the many flight cancellations and airport staff shortage headlines. I got speaking to one of the baggage screening operatives as I waited and he said very early mornings are considerably worse and by around 10:00 things are normal.
He said when security opens (about 03:30 IIRC) there are usually "a few thousand" passengers already waiting to go through and the queue tends to start from around midnight. I got there about 10:30 and it was all OK, not sure if things are any better now.