Dvina has no K4 command, where SNR transmits the missile-target closure speed to the radio proximity fuse of the missile.
You either use K3 against incoming targets, or Dogon against receding.
You can switch it after launch, as it only alters when the SNR transmits the K3 compared to the range boresight

Does the bold one is true for S-75M3-OP?

A question about S-200. In case we are launching against a noise jamming target, after the launch (track on height, azimuth, distance), could we just swich off high voltage and just leave our "ICBM" to do the job alone (like "fire" and "forget")???...