When the bread is proving, the yeast is feeding on the honey in the warmth of the tepid water. In theory the three things that all bacteria need to grow are heat, moisture and food. Any excess of these three things will kill the yeast (as well as salt, which seasons the bread – it’s not half so nice without it, but it does slow down the proving to some extent).
The important thing is not to lose your confidence when it comes to cooking the bread; if you don’t think the dough has proved enough, leave it a bit longer and check the warmth or for any draughts.