IMO, the 30 days delay is excessive, unnecessary and counter productive. Being able to make changes to security verification information quickly but safely is essential. My PC is now effectively hijacked by Microsoft because I wanted to change the mobile phone number I use to verify my security details.
Actually, I wanted to add an additional contact number and e-mail address but seemingly I cannot do that in Windows 10. Other systems, such as Facebook, Google, Twitter, Yahoo! etc., allow multiple phone and e-mail contacts to be used to verify identity and authorise changes.
If Microsoft were a serious OS developer, they would have implemented full biometric security in Windows Hello for all devices whereas it only seems to support certain mobile and portable devices, specifically Microsoft's own Surface products.
I have three HP laptops running both Windows 10 Home and Pro, each of which has a built-in camera, but Windows Hello "isn't available on this device" so I can't use facial recognition on them!
Anyway, surely if I have access to the current mobile phone or e-mail account to authorise the change, that should be enough. The likelihood that both my phone and laptop would be stolen whilst logged in (to an Administrator account in the case of Windows) with their screens unlocked is extremely unlikely.
If Microsoft is trying to protect me from myself by assuming I'm an idiot then they should at least allow me to make that judgement myself!