Want to install on a brand new Fairphone 3+ running Android 10

[TypoSpotter]

I have bought a brand new Fairphone 3+. It is running Android 10 but is prompting me to upgrade to 11. At the moment the Fairphone website only provides links to Android 11 images.

So I have two questions:
Q1 - I think I already know the answer to this, but I want to check: the ubports FP3 page currently says Ubuntu Touch OS for FP3 is built on Halium 10.0, therefore needs Android 10? Therefore does this mean I must not upgrade to 11, and if I do, then I won't be able to install Ubuntu? I also believe it is then not possible to roll back Android to 10 from 11, is this correct?

Q2 - As I cannot find any downloads of Fairphone OS Android 10, I cannot restore Android 10 can I? So if either the install doesn't work, or if I decide I don't want Ubuntu Touch OS anymore, then I must install Android 11?

[Luksus]

@typospotter

1. Yes, you need Android 10 "preinstalled", if you want to install UT.
   You still can go back to Android 10, if you already updated to Android 11. The UBports Installer config for the FP3 provides a link to an Android 10 stock rom, to roll it back.

2. No, as I said in 1), there is still an Android 10 rom available, see:
   https://androidfilehost.com/?fid=7161016148664802137

[TypoSpotter]

@luksus thanks for your answers. I have just finished installing UT and the installation was seamless. I'm impressed with this ubports-installer.