How on earth I need more T4A than T7B?

I have 7 R4, and 8 R3 7* champions.
I have 9 T7B and only have 3 T4A left. Dude what.

Comments

Its Banquet effect. You need T4A for R3 too. Once your 9 T7B used, you will find again you have less T7B income than T4A

I'm literally in the same position, I have more rank 4 than rank 3 😭