Custom domains by outlook.com has improved over the past years and we've referred friends, clients & other startups who want more to email other than the cPanel 'Webmail' offering to sign up. So many people using the platform and the best part about it was that it was free. Now that Outlook.com has ended this offering, maintaining the accounts as is would be a great 'thank you' to the users that have been using this services from the word go as well as the adopted users who moved from the Google Apps platform after they ended their free tier. 

What Google did, which was maintaining the accounts that had been created was a good thing and hope Microsoft/Outlook.com will do the same. 

Any new accounts can be added via the paid platform (Office 365) which would be understandable. 

Let us keep our accounts as is with the 50 member accounts limit without having to move the accounts to the Office 365 platform.