I’m not sure I understand all of your questions……but I’ll try.
Formula is fed until they no longer want it. They determine when they wean, but it’s usually around 8-10 weeks old. Some will continue to drink formula from a shallow dish even when they are much older. My guy is about 3yo and I give it to him occasionally. I use the lid from a baby food jar. Yes, both your formulas are acceptable.
Heat is recommended until they routinely move off of it. They can dehydrate while on heat so offer rehydration occasionally.
In the wild they will begin to explore outside of the nest at approximately 6 weeks old. I would think that around 7 weeks you could consider moving them to a cage. For long term housing the bigger the cage the better so they can have an opportunity to glide. Out of cage time would accomplish the same thing.
With grays we introduce the block once their eyes are open. I’ve only raised one flyer and I can’t remember when I introduced it, but I’d guess around 5-6 weeks. Cut the block in half until you see him eating it well. It’ll be less wasteful. Provide water when you provide solid food. I use a small water bottle but others like to provide both a bottle and a shallow dish. Put some clean marbles or rocks in the dish so it’s easier for them to drink from it.
Here’s the link for a healthy diet for flyers.
https://thesquirrelboard.com/forums/...ying-Squirrels
And here’s a picture of some types of wild foods they eat.