I didn't see yen saw's post when I wrote this, so here's a kinda double post
Just occured to me, I just put some of the fly pupae to warm up and open into flies, or whatever stage it is right before they open into actual flies, and I thought about your post and thought I'd mention the pupae or whatever it is
You could get some of these and put them in the mantis enclosure, and when they warm and open in a day or three your mantis' will have fresh food. I put some of the pupae in my mantis enclosures, along with opened flies, and they soon open into flies and the mantis gets food, and I don't have to catch the flying flies.
They don't all open at the same time, so you do get a kinda time release thing if you just dump some pupae in the enclosure.
Just an idea for 'time released' feeding.
My mantis' don't touch the pupae, that I've seen, but when they open and the flies start to flying it gets their attention real quick B) They relish the challenge or is it just taking out the annoyance... hmm, I don't know, but they eat them flies.