We have checked with the provided information and we are able to reproduce this scenario “All day event rendering as Two days in week view” when start time as 5/30/18 at 0:0:0, end time as 5/31/18 at 0:0:0 and IsAllDay is true. We have already considered and fixed this. This fix will be included in Vol 2 release which is expected to be available by end of month May 2018. We appreciate your patience until then.
When start time is 5/30/18 at 0:0:0, end time is 5/30/18 at 23:59:59 and IsAllDay is true, appointment renders in the all-day appointment panel at the top, not as like spanning appointment on the entire day. If you still face the issue, could you please share the following details,
# Whether you assigned IsAllDay as true.
# Assembly version used.
# Code snippet or sample with the issue reproducing scenario. (if possible)
So that it will be helpful for us to analyze and provide you better solution.
Regards,
Ganeshamoorthy C