Hello KHearty
Those should definitely be within the character limit.
Have you tried using another web browser when trying to change the details?
Even though you are only trying to change the address can you please confirm that the error is not related to another field such as the notes section as this can only hold 250 characters.
If you aren't using the notes section this doesn't mean that the error doesn't pertain to another area, it might be that a field from before the upgrade was able to fit a certain amount of characters it might not now, we commonly see this with the customers name. I would suggest checking the other fields as well.
The error message should also direct you to which field is causing this error to pop up.
The Serial number should be listed when you click on the business name when logged in, can you please confirm the last 4 digits for me.