Action or Script to locate a Selection One Tile at a Time?

Jesus Rameriz has demonstrated getting past the Generative Fill 1024 pixel limit without the fill being stretched leading to pixalization, and he suggests that the process of expanding the background using Generative Fill in 1024X1024 tiles can be done with an Action.  I don't know you could tell the Action where to locate each selection tile, but perhaps someone like @Stephen Marsh could do it with a script?  Or is it doable with an Action?

BTW  I have placed this thread in the main forum as it is not about Generative Fill as such