Bread-Bakers v107.n002.9

I have the opportunity to use an institutional mixer and oven. I 
usually use my KA stand mixer for bread recipes up to 6 cups of flour.

I want to double a 5 cup recipe that calls for 2 Tbs of active yeast. 
(I would sub instant).

Somehwre I read that , when increasing, never go beyond 2 1/2 Tbs yeast.

Could someone help me out on this?

If I just used my regular recipe and made two batches and combined 
them, what would happen?

Many thanks for any help or direction.

Happy New Year, Fredericka