It is normal after an incident of this type that there may be some aftershocks.
This is not an earthquake where we expect to experience the aftershocks

Of course! But, after so many hours of inactivity, delays in DNS propagation may occur. So all it takes is for a connection to use a DNS path that has not yet been updated, and this problem will occur.
Please note, I am not saying that this is what happened, just that it is a possibility.