Mountains of ice melt in the summer then the water refalls in the fall and winter as snow and freezing rain in truly apocalyptic amounts. Rebuilding the ice mountains to start the process over.
Given that the sun is up at roughly the same amount, and at the poles the sun remains consistently up or down according to the season, I think we can rightly assume these two photos are taken at least approximately at similar times of the year.
Also, are you trying to insinuate that 100+ foot tall glaciers are somehow "seasonal?" Because they aren't.
Glaciers actually do retreat and advance seasonally or on even longer cycles. Some have terminuses that move back and forth literal miles. One of the key indicators of climate change is the fact that globally, glaciers are retreating more than they're advancing on average.
I'm not your thread's OP but I want to know the same question (what were the seasons) because no, I don't know how fast glaciers reach that height either. Nothing about that implies denial of the validity, it's a question to help quantify the change. Varying 10ft between seasons means this is a massive change regardless of season. Varying 100ft, not so much. No, I don't beleive it'd actually be 100fr of change in 6 months, but I could see it being more than 10ft.