Board Thread:Support Requests - Getting Technical/@comment-92.83.217.172-20170923131347/@comment-1117661-20170923151359

English month names are supported by #time function so no need for changes there.

As for displaying "Red" for dates over Sep 14th, "Blue" for dates under Sep 10th and nothing for those in between, the code looks like this. All you need to do is to change both instances of parameter name to whatever your parameter is named (ex. whatever you put in source attribute if you're using portable infoboxes).

Note that this will show an error if the input date format isn't supported (like dates in other languages). This can sometimes be desirable and sometimes don't. If you want it do fallback to an empty value on error (ex. if you use it inside a style attribute – like to set font color), you need to wrap it in #iferror function, like so:

Edit: I used dates from your original post for some reason. In case of a single date when the transition happens, Lord Ghiraim's answer is enough.