So I have 2 domains: seankhliao.com and liao.dev. Both were on Google Domains. At first, I just wanted to update payments, as it was tied to a payment profile in a country I no longer had a presence in (Netherlands). But I couldn't find a way to actually do that. Instead, I thought, I'll consolidate management and billing with my existing Google Cloud account, and transfer it to Cloud Domains.
A straightforward move was denied,
apparently that's the only move into Cloud Domains that wasn't supported.
No worries, I'll just move it to some other registrar, then move it back in.
I moved seankhliao.com to Cloudflare,
chosen because I used them before and their at cost pricing.
When I went to move liao.dev, I realized it wasn't a supported TLD for Cloudflare.
Cogs in my mind churned, and I moved it to Namecheap,
because I used them before and still have the account.
The actual move took only a few minutes,
but it until the next day that I saw the Google Domains console clear of the domains I moved out.
So, now the move back, Namecheap showed a warning that it wouldn't go through: ICANN has a default policy of 60 day cooldown in between registrar changes. However, nothing actually stopped me from complemeting the steps in the Namecheap console. and a few days later (iirc standard for Namecheap), my domain was in Cloud Domains Cloudflare however, enforced the 60 days cooldown, so my domain is still stuck with them for now.
Cloud Domains appears to actually just be a different front for Google Domains, after the move back, my domain also shows up in Google Domains. Additionally, with every move requiring an extra year of registration fees, my next renewal period is 3 years away, diminishing the benefits of the move...