I spoke to Jason, and if I understand him correctly, he agreed it’s a Twitter issue: https://twitter.com/jason_mayes/status/671608680035520512
Not sure where I would test this, as the twitter widget in the twitter settings uses a different and shorter time format, like “2h” instead of “Posted 2 hours ago”.
When looking through the components source code, it looks like it’s handling the date/time at line 264-276 here: