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[PoohBear]

My issue is not that simple. I opened a Premier Support ticket and it has been escalated to the PowerApps engineers. I can roll back to a previous version and publish it. I can then publish the app without making any changes and it wil upgrade to the next version of PowerApps.The moment I mak the slightest change such deleting text from a label and republish I get the error. I also have another app that only some users experience the "The app didn't start start correctly" message. 

[ProNewbie]

Looks like when your app gets updated there are some formulas that do not get converted properly, and are causing this issue, that's something for the PowerApps developers I guess.

Good luck on getting your problem solved soon man !