Milk intake between meals

Hi,
I’ve watch the nutrition video on youtube and I have a question.
If I understand, to generate mps I need to eat enough good quality protein in a meal and then fast for 3-5h after that to generate mps again and if i eat protein between that time it won’t be used by the muscle. I’m currently trying to gain weight weighting 89kg for 1m88 at 20yo and for that i’m drinking around 3L of milk per day. The thing is I usually drink all that milk between my 2 to 3 meals space out around 5h apart. But from the information I think I know now, is all the protein i drink between meals not used from my muscles if I don’t wait 3h? And milk is my main source of protein. And does drinking that milk between meals and not waiting 3-5h without drinking any will not create a mps after the next meal? . If that’s right I probaly only get one mps response per day. Should I try instead to drink as much milk as possible right after each meals and then not drinking any for 3h ?
Thanks for help

What’s your waist circumference?

My waist circumference is 90cm

Yea, I don’t think I’d be trying to gain weight in this situation and certainly not rapidly. I also wouldn’t recommend drinking a bunch of milk between meals. Try to get your protein intake in at discrete meals, if you can.

-Jordan