try this...
list := {}
dbgotop()
index on field->yourfiled to temp
while !eof()
if left( field->yourfield,1 ) == "A"
aadd( list, recno() )
endif
dbskip( 1 )
enddo
lastnum := list[ LEN( list ) ]
newnum := ( VAL(ubstr( lastnum, 2, LEN(lastnum) )+1 )
delete...