Has anyone run into the situation where a new ccASHP is being retrofit with the existing high efficiency furnace?

The GHG website notes:

"Note: The Greener Homes program is intended to provide grants for heat pump systems which distribute heat to the entire home, regardless of whether the system is a central ducted or ductless system. The Greener Homes program is not intended to provide grants for heat pumps that only service a portion of the house such as one or two rooms in the house, or only a home addition. The requirement does not necessarily need to be based on peak-load heating, as this can lead to excessive cycling on/off of the system. In some cases, there may be a home design where the heat pump provides heating to the entire home during the bulk of the heating days, and then a backup supplementary heating system provides heating to the entire home after a certain cut-off temperature for th very cold days.

The specific system needs to be determined in consultation with the mechanical contractor and a sizing guide tool, such as the one offered by Natural Resources Canada. The heat pump system is not typically sized to deliver 100% of the peak heating load as this could lead to an oversized system which frequently cycles on/off. Mechanical contractors should design a system that optimizes the energy savings for a house and increase the comfort of occupants. The design should account for the anticipated heat requirements based on other planned energy efficiency upgrades to the building envelope (such as insulation, windows or air sealing upgrades) in order to avoid oversizing the unit as they can have a significant impact on the heating load requirements of the house."

But there is also a note:

"For central ducted systems, if part of the cold climate air source heat pump listed systems, the furnace or air handler must always be the specified matching unit.

So HVAC professionals can design and calculate, but then it HAS to be on the list? 

Meanwhile back in the Webinar on Hot2000 and heat pumps from July 22, 2021 there is a slide that states:
Only the electric ASHP component of the a hybrid system is eligible for a Greener Homes incentive.

Your thoughts and input are greatly appreciated.

I have shared this with NRCan and they are looking at the wording currently.  The technical group is also looking at Heat Pumps. They are also planning on sharing an FAQ on Heat pumps ideally next week.

The grant states:
Cold climate air source heat pumps (ccASHP)
Install a complete new or replacement variable capacity cold climate air source heat pump (ccASHP) system, intended to service the entire home. (see Note below table)

Having an existing baseboard system should not be an issue.