I don't know if this is a good question. But as far as I know, and as I do it, American English also say "after" other than "past" in expressing times.
For example, a quarter after six instead of, a quarter past six as in British English.
The other difference I know, so far, is that the British use dots to separate "hour" and "minute" in digital times like "08.35" while Americans use a colon e.g; "08:35".
So is what I know, so far, correct? Or are there any other differences that I don't know about?