Like I had speculated before it does appear that the general officer reductions being considered by the Pentagon could impact USFK and other organizations in the Pacific:

On Monday, Hegseth issued a memo that ordered a minimum 20 percent reduction of four-star active-duty positions and of general officers in the National Guard, as well as an additional minimum 10 percent reduction in general and flag officers — with an aim to “optimize” and “streamline” the U.S. military leadership.
The memo has given rise to speculation that the Pentagon could consider a potential change in the USFK leadership as it seeks to focus primarily on countering evolving threats from China while hoping that regional allies will step up to cope with other challenges, including from North Korea.
Reuters has reported that the USFK commander post and the head of the U.S. Army Pacific might be among the four-star positions that Hegseth might look at.
Asked if the secretary’s order for the reduction would affect the USFK, a U.S. defense official said the Pentagon has no announcements to make at this point.
You can read more at the link, but if the USFK commander is reduced to a three star then the question becomes will the U.S. handover OPCON to the ROK military? This would mean a ROK four-star would lead the Combined Forces Command and the USFK three-star would be the deputy. Dropping the USFK commander to a three-star would put USFK in line with the three-star that commands USFJ.
Additionally if the USARPAC commander is reduced to a three-star shouldn’t the Pacific Fleet (PACFLT) and Pacific Air Forces (PACAF) commanders also be reduced to three-stars and just leave the INDOPACOM commander as the only four-star in the Pacific?