Hitting "Clear Splits" on every check also works. 

Another option is to change the option in Preferences, General for automatic transaction recall to anything except "Pre-fill accounts for vendor based on past entries" if one of the other options works for you.

My client is in QB Enterprise Solutions 21 R 15_15.  Does anyone know if this is an issue specific to that version of QB or if Pro and Premier are affected?  Also, is this a QB 21 issue only?  Wondering if upgrading to a newer version would fix it.