User blog comment:MisterWoodhouse/Social Activity, the 2010 Editor, and Unpausing Migrations/@comment-46665393-20201102232500/@comment-1807002-20201102233317

It sounds like larger/more popular wikis are first so smaller/less popular wikis might be last. But Fandom staff mentioned something about multiple factors are considered for the migration queue (or list, or whatever). We do not know the actual order fandom is using on migrating.

Asking to be migrated shouldn't have any affect of you getting a head of the line/queue.

And there is no such thing as "safe zones". All wikis will be migrated but at fandoms discretion/order.