apple-app-site-association

I have a website which is restricted to my country only because all our users are local. We want to support universal links so we uploaded the relavant file to https://www.myproduct.de/apple-app-site-association. Apple support saying that they cant reach the file because our firewll allows only my country traffic. So we opened our firewall to all apple ip range 17/8 but it's not working either and we cant see apple traffic from ip 17/8 to that url. Anybody knows from which ip apple is testing the apple-app-site-association file and what's the frequency of that testing? Thank you

apple-app-site-association
 
 
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