interesting ... mine was more related to the saddle .... because the terry saddles generally made me feel like I'm riding on wood.
But I do think there's a pattern of toughening up at the beginning of the season.
If it doesn't go away you will want to look at how your saddle fits, and if it's the right saddle for you. TE forums are great and there have been discussions about how to measure your sits bones for correct saddle with. I'm tall and have wide hips, so the women's Selle SMP works for me, but it is apparently too wide of a saddle for many women.