A few sites have reported an issue where, after upgrading to the latest release of the plugin, the date for an event previously entered into the system will be displayed twice.
This should not be an issue for anyone upgrading to version 3.9.9 from any version before 3.9. However, if you saw this issue crop up after upgrading to one of the earlier 3.9.x releases, updating will not necessarily fix it. Here is a workaround you can use if you have this problem with events currently displayed on your site.
Add the query string ?clean_duplicate_dates=1 to your web domain and load that page. Example:
rsvpmaker.com?clean_duplicate_dates=1
Then take another look at your calendar to confirm the duplicates are gone.
Database bug – I have found in the latest 3.9.8 that if you select “Include event listing with confirmation and reminders” option on the event admin, it cannot be de-selected after saving and it causes a problem when someone submits a RSVP – times out and goes to a “not found” page. It also stops the sending of an email notification to the event admin. I looked in the database, and found that the selection of the “Include event listing with confirmation and reminders” creates an entry in the wp_postmeta table meta_key field called _rsvp_confirmation_include_event with the long_text ON. By deleting the entry, the check mark is removed and the RSVP post functions work correctly.
I appreciate you pointing this out – and doing the detective work to show how to fix it. Will aim to get a fix out over the weekend.
Fix is out in 3.9.9.1