Updating an old app to the latest requirements and iOS 14. What should I do?

Hello,

I have an old hybrid app used by people who have iOS versions between 11.0 and 14+. 

I want to migrate the app to the native code and, to comply with the latest Apple's requirements, I would like to abandon IDFA and switch to SKAdNetwork.

But I am not sure what I should do.

Should I migrate to the UIKit and update all the old devices to comply with new IDFA requirements, 
or 
should I migrate the app to SwiftUI and update the devices compatible with iOS14+?

Would I still be in line with the privacy requirements if only iOS14+ users will receive the update that changes IDFA to SKAdNetwork?

I appreciate any answer, thank you.
Updating an old app to the latest requirements and iOS 14. What should I do?
 
 
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