[JimDabell]

> So, if I update the copyright...and some copycat sets their copyright say at 2019....who retains the copyright?

You do. You don’t need the notice to hold the copyright. You get it automatically as soon as it’s created. The notice is unnecessary.

But if you lie about the creation date by keep changing it to the current year, and somebody can prove their copy existed before the current year, it might make enforcing your copyright difficult.

You should just keep it simple and use the correct year.