I didn't find it weird because the reply that the op made is on january 25, 2018 which is the rank requirements of jr. member at that time is 30 Activity
Correct, and the account has actually been inactive since August of last year, which was before the jr member demotion to newbie.
Op if your intention on the forum is clear and well defined and aligns with the goals of the forum, then you would have no problem returning back to your previous rank or gunning for a higher status.
You can as well purchase a copper membership to be allowed to wear a signature as a newbie