I don't know of any regionals that have a training contract anymore. I think Compass may have been the last one, and that went away last summer.

You can feel free to quit at any time with no obligation. I know of military bros who finished training, updated AirlineApps with their new type rating and 121 training program completion, received interviews and job offers within a month, and were gone from their regional within 2 months of finishing training.