Tracy Arm is scenic crusing. You will not get off the ship. The times posted is actually the time you will arrive at Tracy Arm and the time the ship will leave Tracy Arm . Same for Glacier Bay. The ship will be positioned at several angles so everyone get a view. Depending on the ice formations and the amt of ice your ship will cruise as close as safely possible to different glaciers.
We too were confused about the wording. We thought we would be dropped off to explore which is not the case. If you booked a balcony stateroom this is the perfect time to have breakfast on your balcony.
Hope this answers your question.
Have a GREAT first cruise.