I don't think that's super clear - it seems to have covered somewhat over 20 miles but more importantly passed over a substantial (4k feet prominent) mountain ridge. That would make reliable control by line of sight radio very suspect and I don't think the operator would have risked it unless they had control by satellite or a high degree of confidence in its autonomous capability. Around the point it passes over the ridge the pilots briefly speculate that it may have encountered some kind of control problem due to its behavior, so perhaps it was being controlled from the ground with an autonomous safety capability... but that still indicates a high level of logistical sophistication since it departed the scene away from where the operator would have been (if we go on the autonomous safety theory it was presumably returning to autonomously land at a site north of Tucson?).