Howdy Raul,
I am sorry this is giving you trouble. That is indeed a bug in our calendar, and one we are currently writing a fix for. It looks like it will be included in the next release of Pro. So here in a short bit you will get notified that a new version is released. After downloading the new version of The Events Calendar it you might need to edit the problem event, select the proper date, and hit save. But once you do that it will be working.
Does that all make sense? Will that work for you? Please let me know.
Cheers!
– Brook