It looks like a very worn plateNo. The plate looks ok.
Here is a comparison between a worn plate and a "fresh" plate:
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(Both are from booklet panes with the same plate number).
Notice the sharp grooves are eroded on the horizontal separations between "light and dark". Also the horizontal background lines are looking like thin clouds, no longer lines. The vignette background is almost fully green as the thin lines on the plate have eroded away.
On the 2c stamp, there is no visible erosion so that plate is relatively fresh.