Although we tend to use the glideslope dot as a gear down point in the sim and at airfields with a low platform height (2,500 feet), BA's SOP's actually call for the aircraft to be in a stable landing configuration by 1,000 feet. On the 747 we'd normally lower the gear somewhere between 2,500 and 2,000 feet to give it time to lock, then select landing flap (you can't select landing flap without the gear locked down without getting a pesky warning).
This timing generally means you're all configured (and cross checked) well ahead of the SOP requirement at 1,000 feet AAL.