Characters who didn't do the UFO JQ last year cannot go to the mine for boost skill this year

After @QuestGuy told me he can't access the crystal mine (which unlocks the boost skill for the UFO mount), I looked into my characters and there seems to be a glitch preventing characters who only started the event this year from entering the crystal mine:

On my end:
Level 200s who did the JQ last year: access.
Level 184/185 marksman who did the JQ last year (evidence: Slime Launcher Chair): access
Level 171 mule who did not participate last year: no access, even after doing the JQ this year


QuestGuy:
Level 14x who didn't participate last year: no access

My other friend also reports he had no access on a level 150 character (a new mule that definitely didn't participate last year). He didn't do the JQ at all this year, though.

I doubt there is a level limit as I remember participating in earlier years long before level 180. I'm guessing whatever code activating the option to go to the mine is only triggering for completion of the JQ last year.