The next check number is never saved. We have to manually update the check number on each check run.

This can happen in two situations:
Check Run: If the default starting check number is changed, the next check number on the Checkbook Maintenance window will not be updated. This is standard Microsoft Great Plains behavior. To break the cycle of needing to update the check number with each check run, update the Next Check Number on the Checkbook Maintenance window. From there, accept the default Starting Check Number each time checks are printed. If the Starting Check Number is ever manually over-ridden again, the Next Check Number on the Checkbook Maintenance window will needed to be manually updated as well.
Blank Checks: If the default starting check number is changed, the next check number on the Checkbook Maintenance window will not be updated. This is a good way to print a separate series of checks as your blank checks without affecting the number sequence on your check runs. The next check run will start out at the same place it would have started if you didn’t print blank checks. However, if you prefer to accept the default on the Print Blank Checks window, the next check number on the Checkbook Maintenance card will be incremented by the number of checks printed.