Changing Jobs during Instance: is it possible?

Hello everyone,

I got 'Hullbreaker Isle' as my Daily high-level roulette (for tome bonus).

When duty started, my party was a Warrior (Me), a Whitemage, and Two Blackmages. I thought to myself it will be a fast run having Two Blackmages to flare up mobs to crisp.

Suddenly one Blackmage types in chat: "And a quick copy/paste job now...."

and poof, she's a Monk now!!!

I have read the notes, but I might missed something. Are we allowed to change jobs after we commence duty and during the instance? (Not a pre-made party / Not Frontlines) ?

As far as I know you have never been able to do that but people use a lot of third party software and hacks so it's probably possible using something.

That is definitely not possible in terms of what is allowed/legal in the game
They would have to be hacking/using 3rd party software

Sounds like somebody was hacking. Should not be possible at all.