Doesn't sound good...can you post a picture? Check out my Monarch website to see if I have a picture that resembles it... Here is a link that might be useful: tdogmom's Monarch guide

In my experience, usually around 24 hours, sometimes more like 36, although as you know often this happens when nobody is around so we don't know. But if you really have to move the lid to feed the others, if you do it slowly and carefully the j's will be ok. (remember out in the wild they'd be getting all kinds of jostling by wind, critters, etc.) I've certainly had to (gently) move an object with a J on it on many occasions, and they usually are fine. Just watch if they are really close to the edge of the lid and their silk could be on the lid AND the container side.

Update on 3 of my chrysalises! 3 eclosed yesterday after approx 4 weeks - amazing experience and so beautiful! Sad news though that one fell from the spot it was holding onto (it was a little windy) right after eclosing. It was crawling in the soil so I put a stick down and it climbed up and I hung it from a nearby plant with a clothespin. The wings plumped up for awhile but never fully finished. I found it this morning dead. So very sad that it made it thru almost to the end to die. Butterfly raising, although so exciting, can be stressful. I understand why people raise them indoors and then release them!

I had six big caterpillars yesterday morning, and only two left when I checked again this morning. I saw this site, and then went back out to look around the area. I found two of the missing cats in a potted tomato plant two feet away from the milkweed stand. One was resting on a horizontal wire of the tomato cage and the other was hanging upside down on a small internal branch curled up and looking just about ready to start forming its chrysalis. Both were about a foot off of the ground level of the pot. They were hard to spot though. From Dallas, Texas.