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We add new users to our list of testers, and some of them are still using iOS/iPadOS 12.5.1, probably because they have older hardware (as do I). I was surprised today when one got the invite email, but was unable to load TestFlight because of the older iPad he is using. I found today on my old iPad mini 2 that I could delete TestFlight and re-install (after saying OK to "using last compatible version"). But, I've read that this is likey because I have other devices that have TestFlight on them. How can I support testing of my App on iOS 12 if my beta testers cannot get TestFlight? Is there a work-around?

I'm having some trouble here -- We purchased an iPad to test our app just as a customer would. I created for this device an apple ID using @icloud.com.I then invited this "user" on iTunes Connect.But the link causes various errors on browsers. Safari on the iPad says "internet connection lost" (a poor message, if you ask me). Safari on my Mac says "... because the server unexpectedly dropped the connection." I've also tried with Chrome on Mac and got "CONNECTION RESET" (on iPad, is says ERR_INTERNET_DISCONNECTED).There are other indications that this is a security issue -- For example, clicking on ℹ on Chrome says "This page is not secure", but on iPad indicates "Identity of this website has not been verified" and "Your connection ... is not encrypted". FireFox on Mac shows "Secure Connection Failed". I'll admit I am somewhat new at this, but this seems pretty basic. Is it something I am doing wrong?