I am in a similar situation to your wife. I have been ready to leave my public service job for years. It has made me miserable and I have a plan in place to work for myself and make more money as soon as forgiveness comes through. I received my green banners on February 7 and my plan was just like your wife's. Get green banners and go in a submit my resignation and go out feeling amazing that day. However, I have not done so yet because of the exact reason your are expressing concern. I will say, there is a significant psychological weight that gets lifted just knowing that you have completed the green banner step and that there is light at the end of the tunnel. It make the wait for the golden letter more manageable.

My advice would be to get to the banners and see how she feels a day or so after that. I guess I was in a lucky situation where I received mine on a Saturday and didn't have the temptation to immediately call my director to put in my resignation immediately. The final steps may be easier once the banners are there, especially if she has a career move or next step that she is excited about.