I agree, check with your Breeder, and continue that type for about a month or so.
In my case, I transitioned to the Wellness S5 Small Bites for about a year. I then decided that I'd let them try a less expensive brand, and put out Beneful Original Formula, which they ate vigorously, BUT would NOT give up their Wellness. They just stood by the Wellness bowl which it was in, and waited for me to put more in it for them. What I "tried" to do was, have a full bowl of Beneful, and just reduce the amount of Wellness a little at a time.
DIDN'T WORK with my guys !
So, I gave/give them both, and they eat Beneful in the mornings, and Wellness in the evening. I leave both available 24/7, and they are regular as clocks, with occasional snacks n treats between those two periods. I am by the way, referring to my adult Dogs.
Now, here comes Ichabod (my new puppy).
Got his brand from the Breeder, but he refused to eat it, and joined the adults in eating which ever type they were eating at the time. I know the puppy formula is supposed to be better for him, BUT, he's already just under 5 pounds, and vigorous as any puppy I've ever raised. He's already going on longer hunts along the Bayou, hasn't caught anything (frogs/snakes) yet, but he's holding his own on endurance, and stays shoulder to shoulder with My Male Sneakers (his Alpha Male teacher), except for a hard chase for some prey.
NOW, bless friends with the Holiday Spirit.
A friend of mine, who wanted to give my guys a Christmas Gift, brought a WHOLE case of Purina-Moist and Meaty "Burger" for them.
I was polite, thanked him for his thoughtfulness, and reluctantly put one of the packs out for my guys. It may have taken them no longer than 15 seconds, to consume it, and just love it, eating it between their regular meals. LOL
So, now I have three types out for them.
I know that many here don't vary on the type/brand of food they feed, but, my guys are as strong as Ox's, healthy, very energetic and how can one argue with that.
Ref:
Moist & Meaty® Chopped Burger - 36 6-oz. Pouches - Moist & Meaty® - Brands | Nestlé Purina Store