My reference to versions was simply one way other developers have used the itch tier system. However, a point of clarification will determine whether this has any relevance to you. If impaid $10 today for release 1.3 (no longer listed as early access), will that purchase allow me to download 1.4, 1.5, etc. when they are out of early access. If I paid $25 today to get 1.4 in early access, will I be able to download 1.5, 1.6, etc for early access? Or do I have to pay for each release separately? Also, if I'm busy and don't download the early access version of 1.5 when it comes out, will I still be able to download it when it drops to a lower price point?
If paying $25, $20, $15, or $10 on itch lets me continue to download newer releases when they hit that price point, then setting matching itch tiers and simply moving releases to a lower tier when appropriate might make things clearer and simpler. If that's not how you intend for it to work, forget the idea. And, maybe no one finds the changing prices constantly confusing or irritating. Just a suggestion.