This has been noticed while testing the Learn Moodle 3.6 Basics MOOC. I am linking to what I think might be a related issue; I am not sure if it is exactly the same.

In the course the open and close times are set for 16:00 and 17:00 (or according to timezones) respectively. However, on the timeline it says the session (Start) 17:00, thus potentially confusing participants. If we remove the close time then the start time correctly shows as 16:00.

We'd prefer to have a close time as well, so plan to set the close time once the session has begun at 16:00 , so participants see the correct open time right up to the beginning of the session.
Is there a better way to solve this?