You misquote me, it was "in service in England" with the 4th FG in late '42 and later the 56th FG, around the same time that the earliest model F6F, the -3 was delivered incidentally. First combat contact for the P-47 was in March '43. See the below statistics:
Model        Ser.Del       #Built
P-47B     Mar-42        170
P-47C     Sep-42          60 
P-47D1-24  Feb-43      6,300 
P-47D 25     Sep-43      6,290  also pre '44 which would put it in MW