QV Voyage 616 A B C D

Anyone know how multiple voyages are treated while onboard (in transit)?

We booked QV (Oct 15-29) and we're on voyage 616c. It looks like we are on back to back cruises from Rome. When I searched I found there are also voyages 616a, 616b, 616d.

When returning to Rome on October 22nd will I have to clear customs in the morning and then attend a muster drill again? Will this impact the shore excursions for Rome?

No, you will only clear customs at your final disembarkation port. You are encouraged but not required to attend the second muster drill.