Because your wording, perhaps unintentionally, made it sound like you assumed the SFT would be judging people who used other English variants unfairly because we required correct spelling. But correct spelling means correct for the variant you use and consistent. Don't spell it color half the time and colour the other half. And it is fiction, so you still might have characters who do NOT use correct grammar and spelling. We can tell the difference. But now you know we don't judge that way, so we'll put it all behind us and move forward happily. In future you might want to ask for clarification before assuming someone would judge against your preferred variant of the language. You might have meant it as a joke. That is not always easy to determine without a context of body language, which would normally be written into fiction but not into this media.