That's a good sign,
@mtrhowe85. I would never trust the "gentle-tug" test to be the defining action though. I always remove my plants to check on rooting. If yours is in some sort of soil, you can just hit the sides of the pot in several places with the heal of your hand, invert the pot, holding your palm against the surface/plant base, and let the root-ball fall free of the pot. Did you actually root the cutting in "dirt"? If so, and IF the pot is large enough, you can leave it in its pot. However, if the root-ball is really full of roots, and the roots have already extended to the pot itself, I would up-pot the plant, root-ball and all. Plumeria, once they root and begin to actively grow, need a lot of root-space. Keep in mind these are trees, not houseplants.
If you do see lots of roots, and whether you up-pot or not, I would not hesitate to water your plant. That's just me, you understand. I would be the first to admit I am no plumeria expert.