Norwegian Breakaway has a few Canada/New England in September and October where bar harbor is going to be dropped from the itinerary based on the port schedule. so far norwegian has not made anything official yet.
If bar harbor is a bucket list port for you, check the port official ship schedule to make sure the ship is scheduled to go: https://maine.portcall.com/#!?tab=2&port=Bar Harbor
according to Norwegian website, breakaway is scheduled to visit bar harbor on September 25, October 16 and October 23. These dates is not on the port schedule, so something is going either with Norwegian or port