Hi!
So I used the cool morning time to evaluate if the MMS+ concrete bolts/anchors from Heco would work with my old patio, in terms of bolting/anchoring a substructure to it.
Mark and drill.
Of course with dust extraction and additionally I blew out the holes, and then used my inspection camera. As you can see, the changeover from actual stone plate/tile to foundation is clearly visible - but there is no topsoil, gravel or whatever. That made me very happy, as it was the first indication that it might actually work. (Could have been very different, only a thin layer of adhesive followed by gravel or the like ...)
So lets try to bolt/anchor a scrap piece down.
First with the cordless 1/2" impact wrench.
Then with the cordless 3/8" impact wrench.
Amazing - that is bolted/anchored down, bomb proof!
Then the removal, to make sure the stone plates/tiles did not split or get damaged otherwise that would impair the bolts/anchors ability to hold the substructure.
Since these MMS+ bolts/anchors from Heco feature counter sink heads, let's see if they did.

Oh, and how they did!
I'm very happy that this turned out to be a viable option now, it saves me a lot of headaches.
Actually, that scrap piece was bolted/anchored down that well, that I'm sure even if a bolt/anchor or two would not seat properly, or one of the stone plates/tiles would split - the others would still hold/lock the substructure safely to the old patio.
Kind regards,
Oliver