I am in Belgium, Brussels has a lot of steep hills.

The frame of the Birdy 2 is different from the one of the Birdy 3 and I am not sure this was installed by R&M.

If you look at Pacific Cycles and R&M Birdy, none of them put a FD on it.

If 52x11 is long enough for your use, put a 42t chanring, 42x9 is the same as 52x11 and you will have a much smaller ratio on the 34t cog equivalent to 52x42.