We did do the high version numbers for alpha, beta, RC etc. leading into 4.0 as well.
You can find some of that here: 4.0 release schedule - go through the version history of that page. Fun times. (Makes me nostalgic.) You’ll note that the release date got pushed back a few times as more betas and things were inserted. You’ll also see version numbers like 3.97 for release candidates.