By looking up the co-ordinates for Wellesbourne I've found the relevant part of the log. 6 aircraft regs, 5 commercials, one Europa!
But I'd still be interested in what the code means. Here is one of the log entries, I have blanked what I suspect was the culprit:
$GPGGA,165817,5211.231,N,00136.549,W,2,09,1.4,682.0,M,47.5,M,,*52
$GPGSA,A,3,25,12,32,14,29,31,02,06,26,00,00,00,2.02,1.35,1.51*09
$GPRMC,165817,A,5211.231,N,00136.549,W,65.000,89,250317,,,A*7B
$PFLAA,2,505,-2600,155,1,******!G-****,0,,0,1.5,8*6E
$PFLAA,0,8719,11571,5489,1,40097D!G-EUUB,144,,172,-7.6,9*4F
$PFLAA,0,21819,5440,9459,1,A76CA3!N578FE,147,,246,0.0,8*73
$PFLAA,0,21287,45650,4376,1,4CA809!EI-EKJ,309,,158,-7.6,9*03
$PFLAA,0,38093,40850,6662,1,405F0D!G-EZFE,323,,204,-10.7,9*27
$PFLAA,0,17570,57470,8049,1,405F12!G-EZTB,323,,207,-12.2,9*4D
$PAWRT,4020EC,1,1,1,0,0,0,*41
$PAWRT,FF4310,0,1,0,0,0,0,*47
$PAWRT,FF3210,0,1,0,0,0,0,*41
$PAWRT,FF1330,0,1,0,0,0,0,*40
$PFLAU,0,1,1,1,0,,0,,*63