Patcher for an iOS Unity 3D game

Hi I was trying to build a patcher for my iOS mobile game using asset bundle which will allow the game to be patched without the use of app store update.
But I realized that I won't be able to have any updates on scripts during runtime.
Then is it possible if I make the patcher and the game seperate, and make it so that when I start the app, it runs the patcher first without starting the game, patches everything, and then allow the game to start?
If this is possible, can I be introduced to methods allowing this to happen? Thank you.