Apple iPhone 5s might get iOS 12 according to WebKit test
The smart money expects that for the first time, the Apple iPhone 5s will not receive the next version of iOS this September. Last year, the cut-off model was the iPhone 5; any iPhone that was released after the iPhone 5 received iOS 11. With that in mind, one could come to the conclusion that the Apple iPhone 5s would be the cut-off model this year and iOS 12 will be made available to the iPhone 6 and later.
But thanks to the open source nature of WebKit, the browser engine used by Safari, we were able to find a page that mentions a test run in January that included an Apple iPhone 5s running iOS 12. This is not a guarantee that those with the iPhone 5s will get one more year of running the most up-to-date version of Apple's mobile operating system. But it should give some hope to those still sporting the phone.
source: Macgeneration (translated), 9to5Mac
We should know for sure when iOS 12 is unveiled during WWDC 2018. The annual developers conference begins June 4th and runs through June 8th, and will take place at the McEnery Convention Center in San Jose, California. If you own an iPhone 5s, keep your fingers crossed.
Excerpt from WebKit test showing that the Apple iPhone 5s was running iOS 12
source: Macgeneration (translated), 9to5Mac
Things that are NOT allowed: