I have found the following misleading behavior when playing multiple chars/twinks in the same guild: when you create a guild event with character A, and then relogon with character B, being in the same guild, you will get the invitation as usual (since you are guild member). However, for a GUILD event, you will get the "delete event" button on the lower left hand corner. when you klick it, GC will ask if you want to delete the event, also giving a warning that deleting will also delete the event from other players' calendar. If you hit OK once more, you will receive the error message that this invitation cannot be found (where my assumption is that this is because char B is not the owner of the event). Note that this is different from PRIVATE events where you will not get the "delete" button, but a "remove this event from your calendar" button. Also, this is different from the builtin calendar, which won't allow deleting a foreign guild event either (delete will be greyed out). I am asking in detail because I have recently seen an issue where a complete different PLAYER (not only a char of the same player) was able to delete one of my own events, although neither being owner nor co-admin for the event. I don't believe that the blizzcal API would even allow that sort of operation but wanted to give a heads up to be sure. I was not able to repro the issue with my twink guild yet.