That would be extremely silly and force people into PvP if they didn't want to do it but happened to like the set.
just call it the easy way 1 2 3 4 5....
AF1 - from job quests
AF2 - from myth tomes shop
AF3 - the new set
They will just update the current AF2 models (yes, the Mythology set), because no one likes them.
I always thought of the Myth set as AF2 but as Yoshi had "AF2" on the sketches of the new armour I'm going to now assume the Myth set is AF+1 (It makes sense as the Myth set is the same design of the standard Artifact gear just with upgraded stats, like the Relic weapons and +1 Relic weapons)
I call it Relic armor, and no amount of "agree with me or you look dumb" threads will ever change that. that is what i am used to from FFXI and that is the name i am sticking to.
It is just he said. You are misunderstanding >_>
What we will get is updated design of our current AF2 for those we saw in the live letter. I can guess they hadn't time to polish and/or design the AF2 in time so went with some neon like colour and a part with different colour due the tight time they had. Now since game was released and they could work more relaxed and adding more stuff to patch 2.1 they took the opportunity to put the design they really wanted from start.