I believe those ships with new white pennant numbers will be joining the rumoured new indpendent fleet escorting CV16, an experimental/training aircraft carrier combat group.
W will have to wait to see after CV16 completed her current sea trial if this is true, but I am willing to bet on my speculation.
I think that might be unlikely. The vessel is a Type 054 with HQ-7 SAM system instead of the area defence HQ-16 on newer Type 054A's. I don't think the Chinese navy will risk putting their carrier under the protection of the HQ-7 when they have so many HQ-16 vessels to use.