Definitely.
The earliest ones, like my old one, had Ritchey dropuots where the later early ones from 95/96 had Paragon. All the early ones had True Temper tubes, and the lore at the time was that they were built from tubes that were left behind when Fat moved to NY, though I suspect if there is any truth to that it is more likely that it was an order for tubes that Fat backed out of and young IF decided to purchase. The IF boys were really sensitive to comparisons to the Yo. I remember Elmo getting pretty worked up about it when some of us at the shop were making direct comparison. He made sure to point out the differences, like no domes stay ends and downtube cable routing.
Also I think, though I am not 100% sure that the early frames were straight gauge and not butted tubes.