Underproofed?

I used my usual recipe for Challah (Rose Levy Berenbaum's Sourdough Challah).  Ordinarily I make four small challahs from the recipe, but it is really designed for only 1 challah.  Since we are having our great "Hanukkah Conflagration" tomorrow night, I decided to make only one challah from the recipe to feed all of our guests. 

It shaped up nicely and quickly doubled in size on the counter.  I did the finger press test and it seemed proofed.  It could probably have gone a bit longer, but it was ready enough.

The oven spring was unbelievable.  It more than tripled in size--quadrupled at least, maybe even more (sorry, no pics).  I could not believe when I took it out of the oven, it's gigantic.  It lost some of it's lovely shape to the dough stretch, but you can still tell it's a challah (I made a round one with four strands). 

I have no idea what the crumb will be like because we're saving it for tomorrow night, but do you think it was underproofed?  I did not expect that much oven spring, and it's not very pretty as a result.  The smaller challahs I make from the same exact recipe do not seem to have that much volume.

The only thing that I did differently was do the first bulk fermentation in the fridge.  Ordinarily I do not do that, but because of time constraints I had to make the dough Tuesday night so I could bake it last night.  Would that account for it?  Last night I let the dough warm up to room temperature, stretched and folded, and  allowed it to rise again before the shaping stage, just as the recipe is written (two stage bulk fermentation usually at room temperature, then shape, proof, and bake). 

Fortunately, I checked the internal temp with a thermometer when baking, so I expect that it will be fully cooked, and hopefully with its usually light and fluffy texture.