[Retros] Where are the 3 missing pawns

[Éric Angelini]

Hello Retro’s fans,
this is more a chess puzzle than a retro composition, 
please pardon me — but the coming lockdown in
Brussels has confused me, sorry (I hope the puzzle 
is sound though):

r3k2r/8/8/8/8/PPPPPPPP/RNBQKBNR/8

The above FEN position was reached after ply 22.5 
of an orthodox chess game. But 3 pawns are missing 
in the diagram: where are they?
Best,
É.
Catapulté de mon aPhone