I noticed this today after renaming a couple of my upcoming events. After saving them not only the name was changed but to my surprise the start/end times were gone as well. Steps to reproduce this:
Open web interface, navigate to 'SCHEDULE / Events'
Add a new event, fill in name, date, start (and possibly end) time, choose user(s), save
Open event again from event list, change name and save
Voila, the name is changed, the date remains unchanged but the start/end time is gone.