I was interested to see how the two ovals in the NPR have interacted over the last week or so. 
Using WinJUPOS I derotated my image and that of Chris' to match the longitude of the interacting ovals in Clyde's image before producing this animation.

Most interesting. Chris' image shows that the more northerly oval, initially on the f side of the other, 
has a slightly reddish tinge. 
As it has moved across the interaction is clearly shown in Clyde's image. 
My image shows that they have appeared to merge and the new oval is larger, 
however, there is a smaller slightly more intensely red spot on the p side of the new oval. 
I guess it remains to be seen if they will stay merged, whether the small red spot will rotate around and be incorporated, 
or whether it will separate and go on its way.

I am sure there are more experienced and learned people than I am who will have a view.

--- JOHN ROGERS Answer ---
Hi Niall,

Many thanks for pointing out that apparent merger of white ovals and providing that animation of it. 
In your last image, May 26, the event does not appear to be finished yet, 
so I hope observers will continue to track it urgently if hi-res images are possible.

The two ovals are in the NNTZ, and are probably NN-WS-6 (the preceding one, bright white, 
long-lived) and N3-w1 (the following one, slightly reddish. N3-w1 was an AWO that, 
uniquely, crossed from the N3 domain to the NNTZ in 2021 Sep., 
and it may be the orange anticyclonic oval that JunoCam imaged at PJ41 (described in our reports). 
Unfortunately the pair were not in view at PJ42.

It's also notable that in Clyde's methane images, the pair became very methane-bright when in contact on May 25.

[Niall MacNeill : Wattle Flat,NSW,Australia]