How do you mass remove birthday/anniversary details in People?

[overtheorize]

Hi, Windows Central!

Complete newbie here. Just switched to the Lumia 950XL from the iPhone 6.

Anyway, all my contacts synced from Outlook Live have birthday and anniversary details set to 1/1/1916. How do you remove this without going through each contact one by one? Help would be greatly appreciated!

 

[aleunge]

I don't think you can batch remove all birthdays on the phone unfortunately. You might be able to do something on the web/desktop version (or export all contacts in excel or some other format and delete from there, and then reimport?). An alternative would be just to hide the birthday calendar from the hamburger menu? How did this even happen, was it some importing side effect?