How can I believably change the color of her shirt to white?

[We Run Hollywood!]

Hello!

I am a photographer, I did a headshot of my client today and she unfortunately didn't have any white clothing available so I need to change the color of her shirt to white, and make it look believable. I watched a tutorial on YouTube that helped me tremendously, I feel like the effect I achieved so far looks very convincing.

My question is, how do I include the areas of her shirt that are underneath the strands of hair? To give the most realistic result. 

Thank you so much for all of your comments and feedback!

[Mylenium]

Since she has nice black hair that would provide excellent contrast it could be as easy as playing around with the advanced, AI bolstered selection methods or creating a custom channel with Image --> Calculations that can be converted to a selection.

Mylenium