Very slow proof of Challah

I have been baking challah for many years. Lately, although the end result is a beautiful and tasty loaf, I have been surprised at how long the dough takes for a final proof, after braiding. I want the dough quite puffy before baking, and it never quite gets where I want, even after 4 hours. I don't think it's a longer proof now. I'm just surprised as I have more experience (but never enough) baking bread.

The recipe includes 100% KAF AP flour, 42% hydration, 22% sugar (we like a sweet challah; split between sugar and honey), 4% yeast (fresh package of SAF-Instant Gold), 2% salt. I am in South Texas (plenty of humidity; kitchen temp 74 degrees F).

Are you surprised by a 4 hr proof? If so, any ideas as to why it's so long? If not, should I just relax and let it proof for as long as it needs? Thanks.