Has anybody else had this error in SIMS Spring census?

Error 2510 - For pupils no longer on roll the attendance sessions possible is missing or invalid
It only happens (for me anyway) with students who were put on roll on the first day and taken off the same day because they never attended and were found to be at other schools. It may also be worth noting that the first day was an inset day for us so they weren't expected in anyway.

It appears to be a bug, whereby rather than SIMS reporting the number of possible sessions as 0, it returns a blank thus causing this error.

Has anybody else had this problem? How did you go about fixing it?