Well I'm no super pro at that issue but I could think of oxalic acid and neutralizer that is found at Ben Moore but it is a royal pain to use especially on an important project. Then wood brightener comes to mind, and if neither of those seem appealing then just sanding.
There were water stains on the cedar ceiling in the caboose I made a thread for... I sampled oxalic acid/neutralizer and sampled brightener on scrap cedar. It took some patience to mix correctly in a small batch, have clean buckets, and rinse well enough. Then you have to do all of the surface so it's a chore, sort of. I ended up sanding the stains out because I wasn't gonna do that routine of the acid and rinsing twice to the whole ceiling. It worked.
That lacquer undercoater doesn't affect me affect me...
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