Always On display

I'm updating a timer app that is written in regular Swift. After being built using watchOS 8 the display stays on (Hooray!) but none of the text elements update (Boo!).

I've read the documentation at: https://developer.apple.com/documentation/swiftui/text

But this suggests that the only way to get the Always On display to update is to user SwiftUI.

Please tell me this is not the case.

Always On display
 
 
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