I have also had mild cases in my cutthroat finches, but I have found that if the birds have access to all of the calcium sources that I mentioned, and if they have adequate light, and adequate rest periods from breeding, then they are fine. I would like to add two things that might help everyone avoid this problem. Also having a large cage or aviary so they can get lots of exercise will help. I have found that once a hen has the problem, she has to be watched very carefully in the future as she will be more inclined to have it happen again. I have found that certain types of finches ore more vulnerable.
Cutthroats seem especially vulnerable.
I agree with giving her a rest for a year. Also make sure she is plenty warm when you try to breed her again. Cold often causes egg binding. Ilsa would generally be egg bound for two or three days and be fine. This last time it was five, and unfortunately she didn't make it.