Eric, it clearly says 28 on the end, but it would be more logical if it was 22, as with the sequences for this contract the last 2 digits for the frame number are the same as the last 2 digits for the C number, all the other bikes in this contract have this.
So probably a fault with viewing the number on the bike or written down in the cards, it did happen.
What's more worrying is that this number is not included in the Key Cards Excell file, very strange!
The info on this ERM numbe further gives details that it was at 16BVD, B.A.O.R. and struck off on 20-02-1969