Hi all, a brief update on this feature.
We have had some discussions about what is the best way to introduce new APIs on the IC. We want to expose new APIs to let developers experiment with them and to solicit feedback. It is possible that based on the feedback we get, it turns out that the API needs some adjustments. And if developers have deployed canisters using the API, then making adjustments will be difficult. So we are planning on coming up with a process that allows us introduce APIs in an experimental phase. I’ll make a separate post about the process after some of the ongoing discussions have concluded to solicit feedback on this process.
I imagine that the community will not want to block the release of this feature / API till we have figured out what the best way to do experimental APIs is yet. So, the current plan is that when we release this API, we will document it as being in experimental phase and ask developers not to use it on any critical canisters yet. And if based feedback, some adjustments to the API are needed, then the existing canisters using it will be impacted. We will of course discuss and announce impending changes so that the everybody has an opportunity to upgrade their canisters. We will also have to figure out what to do if someone removes the controller from their canister and then they cannot be upgraded (hopefully no one does that 
)
I apologise in advance for any difficulties this might cause you. And I hope that you can appreciate that introducing a process to iterate on APIs will allow us all to build a better IC without a lot of cruft. Thank you for understanding.