the "A" stands for Automatic [transmission]. The tags on the boot lid never have the "A" after the model designation (be it 633CSi, 325i, 525iX or whatever). Though it is to be found on the user's manual and any other printed matter, even the VIN tag.
Concerning the quantities built of each model www.bigcoupe.com/buying/datesandnumbers.html
will help you.