Best time Tracy Arm?

[LindaKE]

When is the best time to cruise Tracy Arm? Some posts seem to say that early is better because later in the season, there is so much calving that Tracy Arm gets less passable. Others seem to be saying that if you go later in the summer, it may not be as frozen in so you might get farther up Tracy Arm. I know it is just luck if you get to Sawyer Glacier, but am wondering how to raise the odds. We'd love to do the Tracy Arm excursion out of Juneau, but I tire so easily that the length of the excursion seems daunting. We're starting to plan another Alaskan cruise and are trying to sort through the many options that would give us the most exposure to sights we missed the first time around. Right now I'm just trying to get as much info as possible on various options.