Downgrading Account Plan from Lite to Starter

Hello hello!

I’m trying to figure out the effect of downgrading my account plan on my client.
What happens if I downgraded my account plan from Lite to Starter while having only one site on my account and it has a client billing setup?
Is my client going to be able to renew their site plan or not?
And is the published website will be unpublished even if it has an annual CMS plan?

Thanks a lot!