Whats normal voltage drop from a 4amp load? (210ah)

I got to take some of the blame as it happens to me a lot on forums. I write big long confusing posts and some people dont absorb it correctly. It seems like time2roll followed along just fine. While others are yelling at me saying 12.64v is not fully charged. I was hoping we all agreed im closer to 90% charge from the 5a battery tender and the main question of the thread is should a 4a load make the batteries drop to 12.4v?