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Hi guys,
I own Apple Watch (the very 1st generation that came out – NOT SERIES 1) (Model A1554) 42mm Apple Watch Sport.
I just found out that my Apple Watch is being discontinued regarding the watchOS updates and it will not receive watchOS 5 anymore.

I know that if you are rocking let`s say iPhone 5 with iOS 10 and want to pair Apple Watch with watchOS 4, then you are screwed and you cannot pair your Apple Watch.

However, my question is: Will I be able to pair my Apple Watch 1st generation on watchOS 4 to my iPhone 8 Plus on iOS 12 once the public release is out? My iPhone 8 Plus is on latest iOS 11.4 right now.

Thanks in advance