TBH, mine still wakes thirsty - I can now give him a sippy of water in his cot though and he can open, drink and close it. I still do NF
if L asks, as I'm not guessing, he's asking specifically for milk with words.
Thirst will also depend on the weather, how much he's taken in during the day, etc. I have even found if I send a slower flow cup to daycare with him, he will wake thirsty more than if I send a drink bottle with a much faster flow.
At this age, I'd just have a sippy of water available where LO is playing so he can drink as needed.