We are in the midst of it now. He usually eats 4 oz. about every 3 hours but only went 2 between a couple of feeds yesterday. I gave him an extra bottle right before bed (he ate 3 oz.) and then bumped his first overnight bottle up to 5 oz. Will just sort of play it by ear today.
He didn't eat more at each feeding but ate more often. I don't remember how many days it lasted but it was less than a week. Then he slept a ton for 2 days.
I can't say LO has had a specific growth spurt (9 weeks today). He has days where he's a bit fussier and sleeps less/more - but nothing very consistent. He's pretty consistent with eating. And once he increases his ounces he doesn't seem to ever decrease them again.
Re: 6 week growth spurt
So, I guess his growth spurts last a day or two?