Which Ubuntu version is best to work with Legato framework?

I am going to setup PC for CI to work on automation for Legato framework project based. I have two options, whether to use Ubuntu version 18.04 LTS or 20.04 LTS. Any advice? Any known issue on either of them?

I used Ubuntu 18 and it seems to be fine.

Thank you @jyijyi , just curious why not version 20.04? Any known issue?

you can have a look here: