Setting up NHS Mail 2 in Evolution v3.22.1

I've had a number of issues setting up NHS Mail 2 in Evolution and after having installed Ubuntu Gnome 16.10 this weekend I decided I'd have another go.

First of all, I had to add the Evolution EWS service which wasn't installed by default:
sudo apt install evolution-ews

Once that was installed, I was able to go through the account setup:
Edit > Preferences > Mail Accounts > Add

The auto discovery failed, but by manually setting the type to Evolution EWS I was able to get it working.

The magic URL that worked for me was:
https://mail.nhs.net/EWS/Exchange.asmx

Once that was set, I was able to get the OAB URL too by clicking on the Fetch URL button.

The critical step was to set NTLM as the authentication type rather than  Kerberos. The option to discover auth type kept saying that Kerberos was valid, but when I tried it I kept getting an SPEGNO error message saying authentication had failed.

You have to be careful not to store your NHS Mail 2 password in the security otherwise it will eventually lock your account. Still working out how to remove it tf you have done this as I can't find the password in seahorse (Passwords and Keys). If you do accidently store the password in your keyring, you can find and delete it by running seahorse from the terminal or Passwords and Keys from the GUI and search for Evolution Data Source.

I'm not entirely sure that NTLM on EWS is a good authentication method to use with NHS Mail 2 so I will be following this up with Accenture when I'm back at work - Not sure what kind of reception I will get to that though.

Anyone have any thoughts of the merits of NTLM vs Kerberos authentication in an Internet facing application such as EWS?