How have an editor script survive scene activation

Hey there,

I'm writing an editor script that's intended to open several scenes and perform actions on them. That's great; I can cycle through all the scenes and do whatever I want... Except actually hit "play."

If I set EditorApplication.isPlaying = true, my editor script will continue to run - but any delegates I've set (say, for EditorApplication.update or EditorApplication.playStateChanged) will be trashed and can't be reinstated. Any static vars I've set in the editor script are trashed and I can't continue operation of the script after a time.

Is there a way to have static vars in an editor script saved? Is there a way to have delegates survive a change in play state?

(Currently running 5.3.0f1)