We went the length on this versus some HD's some time ago (here is one post which summarizes and responds to much, by God's grace) and it became apparent that certain advocates, one in particular IIRC, unreasonably zealously contended for this despite the evidence against it, like as RCs so often do.
Thus extended attempts at reasonably debate. The hyper doctrine seems to attract a certain exclusive mentality.
I remember. I also remember we could not get the opposing view to 'nail down' a 'time' where this gospel transition happened. We never got an answer then, nor am I getting an answer now.