Transmogging tier pieces

[Lemonwolf2]

If you transmog a tier piece and later on, upgrade that tier item. Does that remove the transmog so I'd have to re-transmog the new tier piece?
I mean the tier pieces from ICC, so upgrading it from 10 man to 25 man for an example

[Thydus]

yes, it'll remove the transmog when you upgrade the item it creates a brand new item.