"The official launch time for Apple Music is June 30 at 8 AM PT, per a Rogers’ blog post and Facebook event, at which time iOS 8.4 will be made available for users to update their devices.
iOS 8.4 is required for Apple Music, which shouldn’t have too much
impact on adoption; Apple enjoys likely the steepest upgrade curve
anywhere for OS upgrades, and it’s unlikely that 8.4 will run into any
issues like the size constraints that prevented some from updating
immediately to iOS 8 when that major new version launched. . .
. . .the traditional history of iOS updates is that the debut window
for the software can encounter issues that delay availability of the
software, due to things like a whole bunch of people all attempting to
access the update from Apple’s servers at the same time."
Apple Music Launches With iOS 8.4 At 8 AM PT On June 30 | TechCrunch
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