The Fox Valley 20/50 is supposed to be for 4 weeks + but I would dilute it and work up to full strength carefully. We have had a lot of babies have real issues with it after being transitioned from esbilac. If they are on esbilac now, I would get some of that to start them out and go very, very slowly with a transition to the FV. Don't get the FV 32/40.
For adult squirrels, 2-3 HHBs per day, fresh veggies and limited fruits. Babies obviously are going to eat less. I also always offer the Teklad blocks so they can always have some solid food in the enclosure if they want it. The HHBs go bad quickly because they have no preservatives, but you can leave the Teklad in until they are eaten. Best place to get them is ebay.
https://www.ebay.com/sch/i.html?_fro...eklad&_sacat=0 For young ones you want the 18% protein, for adults, drop down to the 14%. BTW, the 2 pound bag is a LOT of blocks.