Hey Alex 
Since day one the plan for Monzo has always been to offer the best current account on the planet; the prepaid card was launched as a way to beta test the app and build the experience and internal tools required to support a current account.
Unfortunately, this means the prepaid card will be going away - but don’t worry! You’ll still be able to use the current account in the exact same way you currently use the prepaid card! You’ll just get the additional benefits of things like Faster Payments, Direct Debits and FSCS protection 
If you’re worried about having a separate pot of money to draw from than your main account, this is something Monzo are already working on 