Whatever the reason may be: the two objects are still cruising close together. Last Saturday evening, when bad weather shortly gave away to clearings, I shot an image of the couple while they were cruising through Corona borealis on a western evening pass (not the best of conditions).
The trails on the image are faint, but you can see well that the two are close (separation between the two satellites was 0.78 degrees on the image). SJ-12 is the leading one, SJ-6F the trailing one (movement in the image was from left to right).
As the distance of both spacecraft to the observer was 812 km at the time of the observation, a quick calculation on the back of an envelope shows that the 47' separation on the image is equal to about 11 km separation between the two objects. That is still close!