Sounds like some level of merit will be involved:
At the end of the season, all these teams will be dropped to the bottom tier of the league and empty spots will be filled in by promotions from the tiers below. The exact rules of promotion are not 100% decided (more like 90% decided), yet, but it will basically be the teams that made the playoffs, starting with the teams that lost in the conference finals, moving down, and comparing season records, points differential, etc. If you've got suggestions, feel free to make them and we'll take a look as always. We know that it will never be 100% fair, but we'll try our best. Once I figure out the exact order of operations, I'll post it in the FAQ.
No mention of levels at all.