when I get this free binary information from the AppStore, will IAP purchases work for those users who already have a free binary installed?
It depends on how you implemented your purchase function in your application.
After the user has completed the purchase and the application has completed checking checks, if you somehow saved this result locally on the device (most likely you will), the application will work as a premium version if the application is not deleted or the device is wiped off.
Will these current users be able to purchase this non-consumable product and restore purchases?
As far as I know, they cannot if you remove the application from the App Store. Please refer to the frequently asked question in “Technical Note TN2259: Adding App Purchases to iOS and Mac Applications” :
Your product identifiers may be returned in an invalidProductIdentifiers
array for one or more of the following reasons: ...
- If you or App Review rejected your last binary in iTunes Connect.
If you want to make sure that in the "Purchase Management in iTunes Connect" section, edit the "IAP Premium Features" product and uncheck the "Discontinued For Sale" checkbox. See iTunes Connect Developer Guide :
Taken for sale
Indicates whether your in-app purchase has been removed for sale or not. If this field is not checked, your in-app purchase will not be available for in-app purchase. Please note that if the “Allowed for sale” setting is set to “No”, all settings for the In-App Purchase will still be editable in iTunes Connect, and you can change the “Allowed for sale” at a later date.
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