We have had this happen a few times with our domestic packages, although typically within a shorter duration than what you are experiencing. When it’s happened-
-“Scheduled delivery Wednesday “
-Thursday- “Your package will arrive a bit later than expected, but it is still in transit!”
-Friday-Monday- “in transit auto update”
-Tuesday- “item delivered to …”
It does happen and there is no issue, however it is always best to be cautious, and the most you can do is allow a bit of time to see what happens. One question, had it updated stating “arrived at local post office “?