Hmm, I went back to the DO Buyer's Guide and realized that there's no max number of extensions, my bad.

The Balancing Phase runs for at least 60 days, with the potential to introduce additional 30-day terms if needed. If this comes to pass, the extension will be announced two weeks before the intended end of the Balancing Phase.

However, from this part in the Buyer's Guide, the current balancing phase is almost nearing its end on 26th Feb and they haven't announced yet another extension, so according to what they wrote this has to be the final extension. They might still extend though.