Hi! My advice here would be to make a temporary guild with your guild name to prevent anyone taking the name when you Transfer anyway, as guilds can be deleted easily enough this will prevent any sniping of your legacy. So option (B).
Also you’d be best to contact a GM ingame to get the guild names sorted out for the Transfer, my advice for now is once you’ve made the new guild have the Guild Master on the new realm reach out ingame so a GM can make a note of this matter for future reference. We definitely want you to be able to continue playing under your established Guild Name.
We don’t have an ETA on when the services will be available, and no timeline has been publically published. The plan is to still have guild services they just needed some streamlining and bug fixing.