Varied spellings of words, even within a single document by a single author were not uncommon as late as the 18th Century. And when it comes to usage, the UK, US, and Oz/Kiwis are nations divided by a common language.
Edwin Newman subtitled the first of his two classic books on language,
Strictly Speaking, with,
Will America Be the Death of English?I'm betting that if Newman chose to write a third language book he'd have subtitled it,
The Internet Will Be the Death of English. (Newman died in 2010.) Were such a thing possible, the Internet could be tried by jury for murdering the King's English. (Not to mention the Queens, the Manhattan's, the Bronx, and the Staten Island's . . . )