I did, but last night realized my mistake. I bled the rears until the fluid was cleared out, then I bled the fronts. I had no pedal pressure, and assumed it was the newly installed empty calipers, so I rebled the fronts, but assumed the rears were OK. Turns out I did not take into account Subaru's crossed brake system. The air from the replaced hard line was drawn into the rear left line at some point. I bled the rear enough to get clear fluid, but the air hadn't reached the bleeder, or was stuck in the ABS block. Bleeding the fronts after that did not move it out that way, either.
So last night I did a tedious semi-gravity bleed, which is marginally effective on those front calipers, but still works great on the rears. After a while I had almost a whole brake line length of air cone out the rear left. Definitely enough to make a squishy pedal. Was too late to start the car up and see how the pedal felt last night, but this evening I'll report back.