@snoofle said:
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I told them I would agree to this ONLY if someone else agreed to do the merge - because there would likely be many, Many, MANY merge collisions, and with my dyslexia, I'd likely miss a lot of stuff.
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Do you even have dyslexia or was that just a clever excuse to not to do the merge?
You probably should merge from the main branch to your feature-branch every now and then during the development. Then the final merge would only be six months out of sync. Or someone could keep doing periodical merges for the six months but that sounds pretty silly.