Glance's Calendar Date Header is sometimes wrong

I am using Enduro 3, software version bundle: 11.89.  I notice that the Date Header in Glance is sometimes wrong, but the date of the event itself (the date in the flag which shows upon further clicking) is correct.  e.g. see below: correct date of event is 18th as shown in second photo, but the date header in Glance says Thu 17 (first photo);  the screen in second photo is accessed when same event shown in first photo is clicked.