Bad / inconsiderate driving

On 21 Feb between 05:30-45am I was driving along Malibongwe dr, from NorthRiding toward the N14/R28. As we approached the first traffic light at Cosmo city, a Doppio Zero delivery vehicle was in the left lane, waiting at the red light. As the light turned green it remained stationary. After a while a passenger got out of the vehicle and the driver then drove off. At the following traffic light, EXACTLY the same happened. Then driving at about 60km/h in a 100 zone, I got a chance to pass the vehicle. I moved back into the left, going at a steady 100km/h. Going down hill this vehicle races up behind me, sits on my uhmm *behind, and then overtakes me, moving back into the left lane, slowing down to 60-80km/h for no apparent reason. Not sure of the drivers intention, I passed him again and stayed well ahead of him. I took the offramp onto N14/R28 direction Krugersdorp. On the freeway a security guard was hiking (he's there every Sunday). I noticed in my mirror your vehicle stopping and picking this man up. This driver is inconsiderate and a danger to other road users. unfortunately I did not get a reg nr, but Im sure you have tracking....