Ok, from my understanding you don't understand the mathematics of the tiers, and btw the tiers are made up off cardinalities, so this would make sense. The hole reason 1-A has layers, is because there are higher aleph's. 1-A is stated to be Aleph 2, while Low 1-A is Aleph 1. Now, the higher Aleph's like Aleph 3, would be a higher layer above baseline 1-A, Aleph 4 would be 2 layers above baseline 1-A, etc. Now, High 1-A is a little bit different, it's referred to as a inaccessible cardinal, which is way different too Aleph's. There's not exactly a Inaccessible Cardinal 1, 2, and 3, etc. It's generally just a inaccessible cardinal that is described as strongly-inaccessible, etc. So it would be paradoxical for there to be layers above High 1-A since it doesn't get utilized like Aleph's do. Tier 0 is the same, it's called a Mahlo Cardinal. Again, there isn't something called like Mahlo Cardinal 1, 2, and 3, etc. There is a regular Mahlo Cardinal that is inaccessible to a set of inaccessible cardinal's, etc. You understand? If you need me to clarify on something, I'll respond back.