New Hire Journey - Responsive to Redwood PPM Task

We currently have a New Hire Tasks journey set up as an external URL using the deeplink to the responsive page for Payment Methods.

In a few weeks, we'll be shifting to the Redwood Personal Payment Methods (PPM) page and will need to update the journey task accordingly, and would like to leverage the embedded task type.

Questions: For the already allocated journeys that new hires are working through up until the point when we publish the updated task type, what happens to those Responsive deeplinks? Will they no longer work? Is it possible to somehow keep the Reponsive link available for a period of time as a transition?