Noticed that after upgrading I couldn't send iMessages to contacts via iMessage. I got an error that the number isn't registered with iMessage. Turns out that all numbers now need the country code e.g +44. As soon as I updated the contact to +44 it started working again. Never had this issue before.
Now I have to update my entire address book to change the number format.
Now I have to update my entire address book to change the number format.