You should and can re-register you EPIRB if you shift it to another boat. It is easy to do and you should do so.
I understand that you should....
But say your going for 9 DAY SAIL AND YOU FIND OUT THE CAPTAIN DOESNT HAVE ONE.You go over 5 docks to your boat and grab yours.Throw the lines and go.No time or onboard comp to change it.Is there a penalty for using it?Assumes you let your registered contact number know what was going on....
By the way does it cost money to change it?I never had one.