Recurring events with an end date, when uploaded, are missing the entry on the last day in Google Calendar

This problem is related to the lack of timezone information in the UNTIL=YYYYMMDDT000000Z specification in the recurrence information uploaded to Google Calendar. The time should reflect the event's start time in UTC, and nowhere is this offset calculated/stored in pygpal. (The timezone name is known for each calendar - perhaps tzinfo can tell us from that?)