The plan is to get something out with the Sanctum of Rebirth that is a step in the right direction. Then gather your feedback about how you want to see it evolve in the future, allowing us to refine it before finding an opportunity to go back and apply it to previously released encounters.
There are some comments in this thread regarding harder modes and whether they should have this additional telegraphing. It's definitely something we have discussed, but are open to feedback there!