Hi there!
We just released an update for the Stats - Halo 5 - Player Match History and the Stats - Halo 5 PC - Player Match History endpoints to add support for returning the time component of the “MatchCompletedDate” field. Previously, the Date component would be populated but the Time component would be set to “00:00:00”. Now, by specifying “include-times=true” in the request URL, the time component will be populated. If “include-times” is not specified (or is false), the Time component will not be populated to retain backwards compatibility.
Please let us know if you have any questions. Happy hacking!