Rapid Propellant Transfer

John Hare discusses a concept for dumping propellant from a launcher to a LEO depot in a single orbit.

As I note in comments there, I don't see any need for such a requirement. Once you're in orbit, there's not really that big a rush to come back. The depot has to be in a high enough orbit that it doesn't decay rapidly, so the only cost of staying longer is crew consumables (if there is a crew). Power would presumably come from the depot itself while mated.

But it's not only an unnecessary requirement, it's an impossible one, other than in equatorial orbits (unless you want to wait a very long time for opportunities). Any orbit with significant inclination has a narrow launch window (at least from a given launch site--an air-launched system would have more flexibility). The likelihood that, when you get into the right orbit plane, the station will be waiting for you precisely where it needs to be to rendezvous in a single orbit it exceedingly small. That's why it takes a couple days for Soyuz or Shuttle to rendezvous with ISS. They launch into the right orbit plane, but they have to spend several orbits catching up with it. And the faster they do it, the more propellant it costs.

As I note parenthetically above, though, you can get there directly if you have an air-launched system with significant range for the aircraft (e.g., Quickreach).