I'd love to see even anecdotal evidence of Tiffie or Tempest pilot's using flaps in a fight. I don't recall ever seeing anywhere.
I don't recall ever seeing mention of a Spit driver using flaps in combat either for that matter. Clearly folks have seen it mentioned with 109s. I've seen combat flaps mentioned in combat reports from 51s and 38s.
Quoting the entire section on flaps from the Tempest V pilots notes.
"Flaps Control and indicatior.-The flaps are controlled by a lever(52) on the left hand sloping panal. The Lever has three positions marked UP, DOWN, and VALVE SHUT. The flaps can be arrested in any desired intermediate position by returning the lever to VALVE SHUT. It is important however the the lever be returned to the VALVE SHUT position after the flaps have been fully lowered as when the flaps lever is set to DOWN, the blow off pressure is lower then required for retracting the undercarriage fully. In the event of failure of the engine driven pump, the flaps can be operated by hand pump. An indicator is fitted on the top left-hand side of the instrument panel."