2.8 Smoke Flow Sampling Subframes does not work properly

I have a problem in 2.8 smoke sim. As shown in this pic Particles smoke flow is doted. Altough I seted up 2 of sampling subframes did not changed.

here is the project file. smoke supsample test.blend (585.5 KB)

I think it is a bug as noted on this page. https://developer.blender.org/T61432

I wonder when they fix this bug? Because so important to me now. By the way, I realize it is ok, when do you use a baked smoke sim with 2.79.

Till the bug is fixed, try turning off adaptive domain, that seems to add to the problem. I made a few other changes to produce a stronger solid smoke trail.
ap_smoke supsample test.blend (274.2 KB)