Is the account number always a single letter then the number?? if so then why don't you just go....
Code:
While NOT rsNo1.EOF
Dim accS
accS = rsNo1(0)
Dim first
first = left(accS,1)
Dim second
second = mid(accS,2)
Wend
if the number of letters could increase then you need to do a search through the string for the first numeric character and the break the line on that point.
another thing, if the account letter prefix is always A then why worry about it at all. Forget first and just worry about second.
As for the incrementation a simple second = clng(second) + 1 should do the trick....