No and sort of 
To be more specific, I’m using world rebasing to keep the player and stuff close to them near the origin (to minimize float jitter in their transforms).
At a certain arbitrary (and distant) point, I’ll start logarithmically scaling stuff down to fake distance without actually being that far away.
Interestingly, the engine already supports quite large distances (much larger than 20km) to the degree where I suspect they already have some sort of logarithmic scaling built in.
Which is cool because I only wanted to be doing the scaling thing with really large objects (i.e. planets) anyway.
For the planet meshes, I’m offsetting the mesh vertices so that pivot point is at the surface point nearest to the player (again to minimize float jitter).
That last bit is definitely the fiddliest bit which has held me up for most of this year, but it needs doing because I was getting a small but persistent jitter walking along the planet surface.