Today's ocmments at the Cowen conference in Boston do support the idea that it's OBF but with lower alpha spent on it.... he described the hurdle at the 2nd interim as "even more stringent than usual".
Kirkman and his team are one of the least reliable teams I've seen at transmitting accurate information about statistical protocols. He clearly neither understands nor cares about such things except to spin them. (And from some reliable sources it is clear that the disconnect between what he says and what he should know should he care enough is VERY large)
And again, the sine qua non of OBF is its spend curve. A substantially different alpha spend curve means it isn't OBF. And finally, to add salt to the wound (sorry - not meant to be mean) - that is the excuse you made last time despite multiple statistical folks telling you that was unlikely (in the extreme). And despite the difficulty of finding ANY example of something referred to as "OBF" (with no modifiers) that was actually very different from standard OBF. Do you really want to repeat that process?