Kate, have you thought about trying Oliver on just the normal formula, like maybe try the Nestle NAN again, and just up his bottles? Like give him more than you normally would?
This is what we have done with caden as the hungry baby formula's were too heavy on his little tummy and he was really grumpy and crying lots.
Oliver might be feeling a bit yucky cos the formula might be sitting heavy in his tummy?
Just a thought
Caden is doing really well on the Nestle NAN and he has 200ml+ most feeds. He is also going through his 12 week growth spurt and eating more than usual today.