If you can get ahold of some live prey today, I would try to feed them today. If they do not take the live today, then I would probably give them a week and try again. I personnalyy do not believe that offering food two days in a row is that bad at all, as that is how I attempt to get my animals to convert from mice to rats. I feed all of the hatchlings rats on Wednesdays. The ones that don't take rats, get fed mice on Thursdays. Normally after a couple of attempts, the mouse eaters will start converting over to rats.

I think this is a similar situation for you. If you are wanting to switch to F/T, then I would suggest offering F/T one day, and if they don't take it, then offer live the next day. Continue on that schedule for a couple months, and I'd bet they will switch over (if that was your goal).