QTGMC can work with 422, so there can be just one color space conversion:
Code:
clip = core.ffms2.Source(source=INVID)
clip = core.resize.Bicubic(clip, format=vs.YUV422P8, matrix_in_s="170m", matrix_s="709")
clip = haf.QTGMC(clip, Preset='Medium', TFF=False)
clip = edi.nnedi3_rpow2(clip=clip, rfactor=2)
clip = core.resize.Spline36(clip, 1440, 1080)
clip.set_output()