Seems strange that it would just switch to doing that. Are you sure that nothing else changed (no other plugins added/updated or theme changes)?
The only updates we had done was wordpress itself and your plug in. Also what is weird is we have another website with it, when picking the date of the event the plug in gives us a 3 month spread to choose from. This one only gives us the current month.
Also just went to go play with it again, now when I go to select the date a single month calendar opens for Sept. I clicked the Sept. 6th to make my test event and hit publish. It then reformats the date as 6-9-2013 so it shows it up in june….
Can you provide a URL where we can see this … and is this a problem in the admin screens, the front end, or both?
Its not publicly hosted to everyone yet. I included some screen shots.
So the site in question when putting in the date looks like this.
http://img.photobucket.com/albums/v251/YoDisMatt/76ceab1d-0af2-43b5-a363-418b1faaac44_zpsad69bf15.jpg
On the site it is working fine on it looks like this.
http://img.photobucket.com/albums/v251/YoDisMatt/d10c0dc9-95a2-4be8-a982-0b3fa4bce44d_zps79af68d2.jpg
The working site makes the end date the same as the start date. The site that isn’t working you have to choose your end date as well. Also once the date is selected it then reverses the month and day, so choosing Sept. 5th as my date will make the event appear on May 9th.
You can see how after I published it, now the month and day have switched spots.
http://img.photobucket.com/albums/v251/YoDisMatt/2b262daa-9f83-4f13-bab7-12b075bf3bc3_zps851dec0e.jpg
The original problem of reverting everything to 1970 has stop. I am going to un-install this plug in and then re-install to see if something corrects itself.
Ok so after un-installing it, re-installing it with, still not working, un-installing it and giving it one more shot, it seems to work properly now. Strange.
That is strange, but great it’s working for you.
