Patching and Plastering - Hard Coat plaster that got wet

I am building a house and they just finished the final hard coat application. That night a sever storm passed through the area. The upper floor exterior is still OSB and has not been sided yet. Rain got through the gaps and caused water damage to the plaster both along the upper floors and also the down stairs along the ceiling and the walls. It's beginning to yellow. How do you repair this and also what steps need to be taken if you're painting over the stained areas?

bump. I need help as I am meeting with the job site super Monday

Is this two coat plaster about a half inch thick over gypsum lath or veneer plaster about 1/8" thick over blueboard?

Actually, I doubt if it makes a difference and if the plaster got wet the evening after it was finished it wasn't fully dry anyway so the wter didn't do anything but stain it.

Let it dry then use a proper stain killing primer and there should be no problem.

Pose this on a painting forum and see if they agree.

It's 1/8 over blue board. Thanks for the reply. I also felt that if allowed to dry, the stuctural integrity will be OK. I really needed a second opinion before discussing this with the builder. I did contact a painter and he also said if primed correctly the yellow staining should not be an issue. Thanks again.