Of course it is not official, just a story from old university classmates who visited station recently to do some maintenance in their speciality area.
Zaporozhye NPP was built buy Russians during Soviet times. It uses very popular Russian reactors WWER that is used on many nuclear power plants around the world. After 2014 Ukrainian operator stop buying rods and maintenance from Rosatom and invited Westinghouse to experiment with replacing Russian made rods with Westinghouse counterfeit ones. For over 8 years Westinghouse tried to replicate original rods without any success. Useless Westinghouse rods was just stockpiled by Westinghouse retards in a barns around station. It is a very bad and dangerous idea to put rods made from some random shit into working nuclear reactor in attempt to sort out those that will somehow work. After taking back Zaporozhye NPP Rosatom had to find all counterfeit Westinghouse rods in reactors and replace them with normal ones. One of reactors was fully loaded with different experimental Westinghouse rods, but hopefully was never runned at some decent power level. Also, normal rods are heavily depleted, since Ukraine did not replace them in the hope that Westinghouse will made new rods for them anytime soon. So, reactors have to be silenced. There also was found a lot of unauthorized by IAEA changes made during experimentations. That is why West tried to fuck with IAEA inspection, even tried to kidnap them and shelling plant in a desperate attempt to hide the fact of criminal experiments on running power plant in populated area.
The market for nuclear fuel is huge, and big part of it is rods for Soviet reactors sold by Rosatom. Usually contracts are many decades long but Westinghouse dreamed to hijack that part of market if they will be able to counterfeit russian rods and impose some king of sanctions over Russian ones. That is why the West so outraged about loosing control over their test facility kindly provided by Ukrainian puppets. It is a trillion market and now they lost it. I suppose no other European country will allow such insane experiments on their power stations build around Russian reactors.
So, it is even not about some electricity shutdowns or anything else. It is about coverup of huge fuckup of Westinghouse.
It is also, fortunately, not about producing some nuclear weapon grade matirials, as some rumors insist.
Hardly IAEA inspection will say something about Westinghouse experiments officially, but Westinghouse will know that they know and so on.
PS: Meanwhile that Ukrainian "Energoatom" company have absolutly no clue about current situation on power plant and never had since beginning of the war. It is not Energoatom station anymore in any possible way. So anything they tell about it is complete fake. They are very afraid of possible problems from IAEA due to illegal Westinghouse experiments so lying non-stop to lay the blame to somebody else.
PPS: Don't take that as absolute truth, I can't check it by myself, but at least that story have no contradictions with other known facts and looks much more logical than any other I heard around.
AFAIK even in 2016 they have huge problems after initial attempts to counterfeit rods failed miserably. May be that is why they so desperately tried to counterfeit Russian rods and begin to sell them to Finland and other European countries ignoring any safety and all that stuff on Zaporozhye NPP. I don't know who bought that fuel assembly business now and how it named currently, but locals tell about "Westinghouse".
AFAIK, they went bankrupt when their counterfeit rods in some Finnish power station began to behave weird and Finns kick them out. All their business of conterfeitng Russian rods was broken and only Ukraine continue to collaborate.
Asked classmate, newest counterfeit rods was made in Sweden around 2021 mostly from US parts. He didn't see any papers, so didn't know how that company named now.