ios12 was announced and demonstrated at wwdc, beta started at june 19th and public beta followed at june 25th
since ios 11.3 it is possible to surpress ios update on managed devices – cause you want to test new releases in your infrastructure – ensure that all of your productivity apps running fine with the new version
it is mandatory that those devcies are supervised, setup with apple device enrollment program or enabled with apple configurator
with current emm vendor it is possible to simply enable/disable this value – otherwise configure a profile in apple configurator, either send it via mail or upload to enterprise mobility management suite and deploy remote
if your device running ios version below ios 11.3 your able to configure global http proxy – with *.pac file your able to redirect apple update url
mobile devices fit enterprise needs
madereal - enterprise mobility - innovation 