Yep, that would mean another changeset is necessary. (You can't go back and modify old changesets, you can only create new ones that undo or correct.)
In this case, I'd say for an informal trail like that, having the feature exist and be inaccurate is better than nothing at all. And given your description of the river crossing, I'd say a ford feature is perfect for that. I went ahead and made those changes. Thanks again!
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            #REVIEWED_GOOD #OSMCHA
            Published using OSMCha: https://osmcha.org/changesets/146478737
            