Try 20 days flying a month as a norm, and probably restricted due to duty hours - not FDP since the nature of the flying is mainly short sectors. 6 sectors a day is not uncommon. Expect about 500 hours flying p.a.
Once on line, the only time your flying will reduce is when a significant new intake are training. Quieter perhaps, but then longer to wait for ATPL issue, and the means to escape to an Airbus paying £40k+ p.a.