From what I understand, the queue is not there always.
There is a very narrow window in spring during which the ascent is possible, due to weather (enough ice to get over some sections, but weather not leathal). If you go too early you freeze or get blown off in 0 visibility, if you go too late, the ice has thawed too much and you get washed off in the rapids.
Sometimes the window is only something like 10 days during which you (and everyone else) have to ascent and descent from basecamp.
There is a very narrow window in spring during which the ascent is possible, due to weather (enough ice to get over some sections, but weather not leathal). If you go too early you freeze or get blown off in 0 visibility, if you go too late, the ice has thawed too much and you get washed off in the rapids.
Sometimes the window is only something like 10 days during which you (and everyone else) have to ascent and descent from basecamp.