Space travel and the Treadmill effect?

I should preface this post by stating that I'm somewhat scientifically illiterate. But I don't want to be!! I have questions. Lots of questions. Maybe even stupid questions...But the kind of stupid questions that only smart people can answer. Well, that's where you come in:

Stupid question #1.

Let's say that I had a spaceship that was capable of speeds faster than the expansion of the universe. A quick Google search says it's 68km/s per megaparsec. And let's say that I set out from Planet A in one galaxy to Planet B in another galaxy. And let's say that the two galaxies were expanding exactly away from one another.

If I successfully made it to Planet B and wanted to make a return trip to Planet A, would I have to travel twice as fast to make it back home in the same amount of time? I mean given that the planets would be essentially running away from one another, is it conceivable that I would be trapped in a sort of interstellar treadmill where I would be traveling say 69km/s per megaparsec away from Planet B, but not actually getting any closer to my home planet because it is receding from me at roughly the same speed?

In my quaint understanding of the world I imagine that traveling between two planets in the same galaxy would be doable because the cluster of matter would be relatively fixed within the same gravitational sphere of influence. But outside of that influence the galaxies would be diverging from one another at a much faster rate which leaves my imaginary spaceship forever stranded in no-mans land.

So, maybe that's more than one question; but that's the gist of what I was pondering. Which of you can set me straight?

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