As long as your bulbs are still firm and not dessicated go ahead and plant them now. Al

This may not help. I had them in basement in pots, they sprouted (in my opinion) way too early. So I threw them outside and left them there, even when temps dropped to 15 degrees. They are fine, but slowed down to be more "caught up" with in ground daffodils. I don't know sprouting till bloom time. Thankfully, they've stayed sprouted, but stilled, meaning not growing much higher. My goal is to have a more "on time" bloom...It's been about 3 weeks of more top growth, except for one. As I said, this may not help..

The question must still be asked. "Why were these bulbs not planted when they were supposed to, last fall.
You are asking "shold they be planted now?"....

Do the bulbs have a basal plate and have roots formed?
If so, go ahead, plant them...who knows, maybe Ma Nature will be fooled and they'll amount to something.

If not, throw them on the compost pile where in time they'll be of some good.
You cant plant spring flowering bulbs, meant to be planted in the fall so they can gain roots, in the spring.
You are 4 -5 months late.