If you look at the "approval" listing we can note the Approval date is different from the actual BTD designation awarded date.

For example, for Bristol-Myers Squibb (Yervoy / ipilimumab), it would appear the BTD was announced in November 2019 (so 5 months separating).

I think other examples from that list similar. So 5 months from announcement would take us to June / July, but who know time frame.