Sorry to hear your trouble. I hope the transition will work well for you in the end.
It really sucks how Epic management, out of greed for more profits from microtransactions in the Apple store, is willing to throw devs like you under the bus, just to make a point. It also sucks how this decision is affecting negatively the great Unreal Engine 4 development team & all the free contributors, working hard to bring out new features.
If there is some hope and this lawyer firm will have their predictions to be true, then Epic will likely go back to the App Store under the old terms very soon: https://www.youtube.com/watch?v=bZkX3pG8biQ
Though I can understand you can’t take that risk.