Wikipedia says they have 4 Crew Dragons in service, 1 under construction.
- Crew 8 is docked at ISS
- Polaris Dawn is on the launch pad scheduled for Monday. It is configured for a space walk, so I think that means it doesn't have the ISS docking adapter installed
- Crew 9 is launching in September (with 2 or 4 astronauts)
- Fram2 mission is in December. I think it is going to have the viewing cupola installed, so no port
I don't know how fast a Dragon could be refitted with the docking adapter so maybe the other 2 aren't available on any sort of emergency basis.
The emergency plan for Butch and Suni until Crew 9 gets there is either YOLO Starliner or lay on the bulkhead of Crew 8 below the 4 astronaut seats, not wearing space suits since the Starliner suits can't be hooked up to Dragon.
> wonder how quickly SpaceX could scramble an unscheduled Dragon launch if asked to?
The better question might be how much SpaceX would charge for having a Crew Dragon with ISS docking adapters standing ready for launch within one week. I'd guess that would cost SpaceX less than $100mm. (The actual mission would be billed at usual rates. You're paying for optionality.)
Last-minute rescue from orbit simply hasn't been something our species has had the technology to do until recently. (Space Shuttle needed 30 days on paper.)
There are four Crew Dragon. One is attached to ISS and one is preparing for Crew 9. The other two are scheduled for commercial flights, one launching in a few days. The later one would have be re-scheduled or do fast turnaround to come up with spare Dragon. There is also one for Crew 10 under construction.
The other question is how long it takes to make Crew Dragon ready.
I don't know how fast a Dragon could be refitted with the docking adapter so maybe the other 2 aren't available on any sort of emergency basis.
The emergency plan for Butch and Suni until Crew 9 gets there is either YOLO Starliner or lay on the bulkhead of Crew 8 below the 4 astronaut seats, not wearing space suits since the Starliner suits can't be hooked up to Dragon.