That's the best time to dig them up. By then the bulbs would have received additional nutrients that had been used for the spring/summer growth.
However, if I have plenty of the same I sometimes divide them and given some away mid-season. The recipient would have to be very careful not to break the stalk, that's all, because that would set them back a bit the following season.

I guess I'll wait awhile to dig. By the way, I now have blooming in my yard, feverfew, laitris,and balloon flower from seed you sent me 2 years ago--and I thank you!!!

Oh, you're welcome. I am glad they are doing well.