So either the previous owner returned it to stock just after 25500km and before you bought it.
And when BMW did the check at that time they did not do this FASTA check.
So it means that you had no knowledge about any s/w and over-reving so u should not be held liable. In their checklist is asks them if they suspect any modifications and I guess to read the file aswell, so that's their part, they did the check and was happy to sell it with plan.
On the other hand the car probably still has software on it which was never picked up by them and it also show's how "responsible" of a driver you are cos if they check from 28000km to 40000km there is no over-reving, so this states that u did not abuse your vehicle.
This is BMW's f up, the first dealer who do the transfer when u purchased it.
Also isn't the FASTA thing done on special request cos they tried to take my friends plan away after he got them to replace 5 diffs on his M5 and then they showed him speeds of 250km/h and everytime he drove there and said that although it's was stock that he abuses his car. But they never took his plan away in the end.