I think the problem is due to some bugs, this problem shows some frames.
PROCEDURE MakeMKV
These are frames of reference
Frame 2:06:53 (it is not the subforced)
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Frame at 02:30:37 (subforced appears on the next frame of 02:30:51)
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2:30:51 frame (it is not the subforced for this frame)
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PROCEDURE MKVToolnix
With this procedure, the subtitles are correct
Frame 02:06:53
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Frame 02:30:51
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