Survo doesn't have GIP, only GLP1 & glucagon, whereas Reta has all three.
In order to keep from a permanent stall just short of my goal, I've switched to Cagri & Survo, which opens 3 of the 4 pathways, exception is GIP. Hoping if the time comes, the Tirz will still work. Wish I'd done all this differently, knowing what I know now.