Wild suggestions:
Hack end cars into centre cars as required
Convert the XC and WC 221s to 220 spec (fully remove all tilting gear, lighter bogies)
Reactivate Project Thor
So, including the two out of use cars, there's 356 carriages across the 220/221 fleet. Form into six car units, that's 59 units + 2 spare cars. Add two pantograph new build coaches to each unit, reconfigure interiors (toilets, buffet counter, etc), voila, lovely fleet of 8 car bimode IC units.
Or 50 9 car units.
Let's go with that.
Add another 20 similar units from the 22x fleet
Leaving 6 voyager and 3 Meridian driving cars.
Hack end cars into centre cars as required
Convert the XC and WC 221s to 220 spec (fully remove all tilting gear, lighter bogies)
Reactivate Project Thor
So, including the two out of use cars, there's 356 carriages across the 220/221 fleet. Form into six car units, that's 59 units + 2 spare cars. Add two pantograph new build coaches to each unit, reconfigure interiors (toilets, buffet counter, etc), voila, lovely fleet of 8 car bimode IC units.
Or 50 9 car units.
Let's go with that.
Add another 20 similar units from the 22x fleet
Leaving 6 voyager and 3 Meridian driving cars.