Last month they stopped accepting Silvers through fast track, the sheet (as of first week in Dec) read Gold card holders only.
Yet again another example of BA cost cutting and making the experience more and more like Ryanair.
Group Boarding is never enforced here and the check in desks will not open a second before T-2h. The staff even sit there behind the desks looking at the queues, and there is often queues for both lines at T-2.
If taking BA851, I’ve found the security lines by the LOT check in desks a lot quieter at this time of day rather than the ones by the BA desk as there seem to be a number of charters that go at a similar time from that end of the airport.