I'm really confused, my letter of approval I got yesterday says ''You should not travel outside the United States until you receive your new Green Card, as you may have difficulty reentering the United States. If an emergency arises and you have a need to travel outside the United States, before you receive your Green Card, you may make an appointment at your local USCIS office to request an I-551 stamp in your passport that shows temporary evidence of status as a lawful permanent resident''.
I'm asking because while I'm 99% sure I'll get my new GC by the end of this week, if I don't get anything by July 1st, I was thinking of making the appointment (trying to think ahead if the situation happens)