They may adjust, but it is getting rather iffy for them, age wise, and the hens may object, which would make matters even worse. To try switching them around after they have come off of the nest isn't easy and would need a very accommodating hen. you need to consider if you feel the risks are worth it or if confining them somewhere for a few hours while you make changes to the fencing is a better choice for them.
Yes you can break the broody who would no longer have chicks, it may take her a few weeks to get 'back to normal', there is a very slight chance she would return to a broody stage in short order though, messing with hen hormones is far from an exact science.