User blog comment:Pualover/Overlord Power Level/@comment-101.127.209.29-20180305181213/@comment-34666853-20180306072611

He can't be 43 because 43 is the threshold entry level for 7th Tier magic. It's not (n x 7) rule, where n is the tier magic a caster has. Ergo, it's not 7x7 gain access to 7th tier. It's "gain access to a new tier every 7 levels" so 7 levels after 35 gain access to new tier. At least that much is clear, I guess.

Frankly, its how levels and classes interact for tier magic is the enigma here. I would have expected after you completed the base-high-rare (aka 30 levels in a class path) you'd have access to the highest tiers of that class. Apparently, from how this all goes, a guy with something like Mage (15) -> Sorcerer (10) -> Archmage (5) still wouldn't get it.