From paid app to free with ads

I'm have an existing app in the AppStore which is paid. I want to update this app to be free with ads, with an In App Purchase option for removing ads.

The problem is: for all the people that already paid for the app, I want to provide the update with the ads removed by default.

Is there any way to accomplish this?

I am looking for the same answer to this question. Thinking we could check a date on the verify receipt maybe so previous users do not see the ads.

From paid app to free with ads
 
 
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