Hm.. not sure what you mean. I was referring to the switch from $observe to this scope.template.
This current change breaks the binding of the currentText (perhaps that's intended).
However, if you do want to bind it, one solution is to use a getter method to fetch it from the scope. 

The getter method can enforce the defaults. This way, if the scope variable is changed to undefined, it still falls back to the datepickerPopupConfig value.