Is greylisting would effect all domains that serve the same email service?
Google is own @gmail.com and @googlemail.com for their email service
FastMail have multi domains, you can check it from here
In a nother words, Multi domains that have the same MX and IPs which belongs to same email service provider.
If my server got a greylisting from @domain1.tld while i'm trying to send an email to it, is that mean i got greylisting on @all_other_domains.tld of the same service?