Exclusions to recurring events using “different day” don’t work

WordPress 4.8.3 running theme55218 theme
The Events Calendar version 4.6.3
The Events Calendar Pro version 4.4.19
I have ‘automatically share my system information’ turned on (System Info Key Added)
My website: https://lutherburbankartandgardencenter.com

I’m using a Pro calendar supported by your nonprofit program (I cannot use pro support forums for this reason). I ran into the same glitch expressed in the support tickets here on the pro forum:
https://theeventscalendar.com/support/forums/topic/exclusions-disappearing-after-updating-page/ (October 23, 2017, submitted by Randy Taylor) (I subscribed to this thread)
https://theeventscalendar.com/support/forums/topic/recurring-events-exclusions-default-to-same-day/ (August 8, 2017)
https://theeventscalendar.com/support/forums/topic/events-pro-exclusion-major-issue/ (November 8th 2017)

In short, if I try to make yearly different-day exceptions to a monthly recurring event series, it switches back to the same-day setting as soon as I save the event. This bug is not listed in Known Issues as of 11-8-2017.

I’ve tried many of the prior suggestions, including:
? Setting WordPress and Event-Start time settings from UTC to my local timezone (UTC-8).
? Ensuring all plugins are up-to-date.
? Ensuring that the exception does not affect the first event instance.
Procedure here: https://theeventscalendar.com/knowledgebase/testing-for-conflicts/
? Creating a staging site, deactivating all plugins except for modern tribe calendar and modern tribe calendar pro, removing mu-plugins and theme overrides, setting the theme to twenty-sixteen, emptying the calendar and its trash entirely of events, clearing my browser cache, deactivating/reactivating the calendar plugins, and then testing on a new recurring event. The glitch was still there.
? Testing newly created events on both Firefox and Chrome.
? Testing from a different IP address.
? There are no browser console errors generated during saving the event or on the calendar page.
? No seemingly relevant errors appeared in debug.log

I used marked screenshots to illustrate the problem:
https://lutherburbankartandgardencenter.com/Content-Holding-Dir/exception_glitch_illustration.jpg

Since none of my testing fixed the glitch, and other people are having the same problem, I’m hoping your staff can look into this soon.

Any advice would be greatly appreciated.

Thank you,
Janet