It was Hero track, and was at 4/5 at the time S2 ended, but it let me upgrade it using only Flightstones? I’m really not sure why? 
Only took it to 441, so it’s not like it’s useful, but I still found that interesting. No S3 items seem capable tho.
Just checked another item, this time my Iridal from S2, at least my old veteran one I never upgraded (I got a better one before I could upgrade it) but it’s letting me upgrade it right now via just stones. Cool.
Also, oddly enough, the ‘dreambound’ blue items I have in my bank that I’ve looted in S3 are now boosted to ilvl 454. So for those folks whining about LFR min ilvl, a full set of the vendorbought green items should see you in, maxed out with flightstones. Looks like nothing but flightstones maxes those dreambound type items up to 476.
So get crackin’ folks that need LFR gear.