User ‘hufden’ of a Russian forum posted another picture, indicating that it is from 29 March 2025,
so it is definitely not an April 1 joke, but the Reuters one is also true.
The photo of ‘hufden’ is of better quality, so I still tried to estimate the size of the North Korean frigate by aligning this one as closely as possible with another in which the floating dock is seen.
The red lines are +/- to fully align the outline floating dock + bow of the frigate with the pier elements of the other satellite photo.
The white lines are what I personally believe to be the frigate's outline.
Already from the dimensions of the floating dock of about 125 metres, visually the frigate is longer.
Then I tried to work out the dimensions of what I consider the outline of the frigate, which led me to assume a length of about 140 metres.
Of course, this is always a measurement made empirically and therefore an approximate one, which in the future will certainly be confirmed (+/-) by experts with new, even better defined images, or refuted

completely.