I personally do Flap 3 once a month only in a 319 as practice incase of an emergency requiring a Flap 3 landing. In a 320 I never do Flap 3
160 to 4 is de rigor at BA unless early rad alt callout or strong tailwind. 08L will almost certainly be flap full due to desire to vacate early.
At roughly 4.4 miles it's gear down, flap 3, flap full in quick succession. Gear must be down by 1000ft. No exceptions.
You're definitely measuring 2.5D from the threshold? Generic Airbus SOP is gear down at 2000ft radio.