[Alex Smart]

Hello,
While I accept that the usaafdatabase you refer to is great for details on American aircraft and crews in general. I would trust the AB details for the British aircraft.
For eg:
Dabney was KIA over Dieppe, therefore his aircraft woulld not have been returned to service as was BL338 according to "Spitfire International",
BL338 - Spitfire F.Vb (Merlin 45); ToC/RAF 15.11.41 - US 8thAF; 31st FG, 309th FS High Ercall 20.6.42; Temp Missing 19.8.42; 308th FS Westhampnett, crashed landing, Cat A 26.8.42 (2Lt.WR Waltner OK); Re-Cat.B; Retd RAF (Repaired in Works, date unknown)
And for R7344:
R7344 Spitfire F.Vb (Merlin 45); Presentation aircraft "Borough of Halesowen"; ToC/RAF 12.4.41 - US 8th AF; 31st FG Atcham, 308th FS 14.7.42; Took off 10.02, missing near Dieppe, CatFB/E 19.8.42 (1/Lt WAM Dabney killed),SoC.

But then a contradiction from
From "BA100 to BZ999"
BL338 - 72/High Ercall/308US - Missing on fighter sweep to Dieppe 19.8.42.
and for R7344
"P1000 to R9999"
R7344 - 91/308 - Missing from escorting Blenheims to Hazebrouck, 19.8.42.

And from Flag3 the MACR (16481) one page has unknown for a/c type and unknown for a/c serial number.

And then from the on line Spitfire Production list:
BL338 Vb CBAF M45 8MU 15-11-41 72S 21-11-41 FACB 14-3-42 ASTH 308USAAF FTR Dieppe raid 19-8-42.
R7344 Vb 1585 EA M45 FF 12-4-41 8MU 12-4-41 91S 28-4-41 Westland 11-4-42 308S 14-7-42 Missing from escorting Blenheims to Hazebrouck 19-8-42.
"Spitfire - the History" has for
BL338
"BL338 - 8MU 15-11-41 72S 21-11 FACB 14-3-42 ASTH 308 USA FTR 19-8". (FACB= Flying Accident Cat B;ASTH = Air Service Training Hamble).
and for
R7344
"R7344 - 1585 - EA FF 12-4-41 8MU 12-4 91S 28-4 WAL 11-4-42 308S 14-7 FTR ops 19-8". (WAL = Westland Aircraft Ltd).

So as you can see the whole thing is confusion.Depends which refs you wish to follow.

Best of luck
Alex