That 10' to 10'8" is for floor-to-ceiling heights, so floor-to-floor heights should be a good bit more than that. A quick analysis of a screenshot from one of their preview videos highlighting the floor slab technology suggests a floor-to-floor height of about 13'. That would yield ~340 feet plus the crown.
I also did a quick analysis of one of their square-on renderings, and assuming that the obvious change in curtain wall is at the 50-foot mark, that scales up to a total height (including crown) of 340 feet.
So there...two more contradictory estimates.