Hello. Glad you found it useful. It's a very difficult one to answer as in my experience very few manufacturers provide load data, also not all are reinforced. My use case is fairly light duty circa 500kg total weight, so across each pier it's very low. I worked on a conservative basis of 200Kg max per pier (with at least 3/4 of them in the ground for stability), and for my 8x6 I think 5 would of been optimal for support (not load). For 10x12 I'd say 9-12 piers would be about right depending on what you are going to put in it + how thick your timbers are.