With Parental Controls/Bed Time setup, the router would allow a game, such as a Fortnite match, or a YouTube video to finish before cutting off access to the internet.  This functionality would always allow my son to finish what he was doing before losing connectivity.  Awesome and very much appreciated.  

Last night, his internet access was cut off at exactly 10pm...right in the middle of a match.  The only change made to the router was a time adjustment, the previous day, allowing for an extra hour of internet time, but I've adjusted times several dozen times in the past and the aforementioned functionality has never changed.

Is the fact that the router has, in the past, allowed my son to complete his current activity before cutting off internet access a feature, or was our experience a bug of some sort.

His PC is hard-wired directly to the router.