I have noticed that this event (https://coord.info/GC7EZRD) is on the same day and is only 13.5 miles away and within 10 hours. Will the event stacking "rules" come in to play? Or because it's a souvenir day will an exception be made? Let's wait and see.
O dear
Looks rather a basic Event, a flash mob type, which would be a great shame if this blocked our CW event. I think an appeal would need to be lodged if it did, as there has been some planning need to be done before the Event location was know and booked and thus an Event cache could be submitted.