If you use P4V, you can easily make a mistake in the GUI. In particular, if you right-click somewhere to select "Merge / Integration ...", then what you clicked will be used as a target, EVEN IF YOU USE A BRANCH SPECIFICATION.
I was puzzled by something very similar to centuries, until I realized that I was pushing on branch B to start the merge, instead of clicking on branch N.
An incorrect GUI reference is what you clicked on, initially shown as a target, but when you decide to use the branch specification, this part of the dialog disappears. It is still present on the Filter tab, but you already forgot about it because the GUI took it ...
William Roberts
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