Henry (green anaconda) bit me again today

I would say the general wisdom on this subject is that by this age he should only be biting me when I commit Stupid Feeding Errors. He's a year and eight months old.

I let him wander around my bedroom for a couple hours.

When I reached to pick him up, he bit me. Then I picked him up, and he bit me. I'm counting a total of four bite marks. He had plenty of time to see me coming, and I moved slowly and deliberately, just like you should.

They were very deliberate bites, like he knew exactly what was going on, and was doing it specifically to get me to leave him where he was. I was far from significantly injured. My only concern is that he cuts this out before he gets big.

j_soo, whose knowledge of snakes I trust the most, said:

You almost certainly woke him up, and he reverted to his biological programming for defense.
I have no evidence, but in many years of playing with many snakes, I'm pretty sure it takes them significant time from waking up to being 'normal'.
Almost like it takes an amount of time of basking before a snake acts normal, I think it also takes time after waking before the brain is entirely functional.
Again, I have no evidence to support it, but I've observed it invariably in every herp I've dealt with.

Last time he bit me was March 18th, under similar circumstances.