This issue is due to the actions I’d performed previously. I was trying to push a new change, on top of a change which was still up for review, who’s parent also was up for review.
Trunk ------ Parent A ----- Parent B ----- New change
(merged) (unmerged) (unmerged)
I had used cherry-pick to obtain these two changes locally (Parent A and Parent B), and then a third cherry-pick to get my change from a local branch before attempting to push. That is what caused the issue, because my personal change was essentially trying to re-write history.
The correct process would be to only pull Parent B when at trunk. This automatically pulls up any commits between trunk and it (in this case just Parent A). Then cherry-pick my new change on top of that and push will work fine.