That "milestone agreement" with Aspire was signed late June, almost certainly pre-submission of the BTD app. Maybe it took us longer to submit the BTD app than we expected. Consider how long it's taking us to prepare for the end-of-Phase 2 meeting...
I do not think we "sat on it", if you're implying forgetfulness or negligence.
Anyway, by far the important thing is that BTD-OM is still a potentiality.