At the time I did not find a solution to this. A few weeks later this blog post led to the answer:
So you have the options to either go through these steps and upgrade it by yourself, or you can raise a ticket with Microsoft and they will do it for you.
We chose to do it ourselves, because we weren't productive with it at the time and we took it as a learning experience as we figured it wouldn't be the last time we will have to go through something like this. I can't recall if there were any difficulties I could point out to watch out for. It just took a while for everything to deploy. As always, I would try it on a sandbox first though.
Hi @Nelson Johnson & @Timo Veneman,This may have changed, but we are currently building out our Project Service Automation deployment, on PSA v3. Because both PSA and FS utilize the Unified Resource Scheduling and share a lot of componentry, they have to be upgraded together. Microsoft required signing up for the insider program 6 months ago. They indicated both were fully supported as generally available, but due to the codependencies, required you to acknowledge this and have MSFT run the upgrade. If this isn't clear on the FS side, try checking the PSA documentation.
It may be worth noting, we've found there are still a lot of bugs being worked out with PSA. I can't say much on the FS side. But with PSA, documentation has been all over the place. The support team has been responsive and appear to be working aggresively to work through the issues, but if PSA is any indication of things on the FS side, and you aren't in a big rush, my experience would suggest it may be worth waiting till the next major update rounds in April if possible. - Probably not what MSFT wants to hear, but that's my view based on PSA.
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