Question regarding setup and extraction of ROI data

Dear Experts

I have a quick question regarding the setup of ROI data. I finished a connectivity-analysis and now want to change a few things, such as masking my individual ROIs with individual grey matter masks. When I chose "mask with grey matter" in the ROI tab of the Setup in CONN, do I have to chose "overwrite existing results" when I want to perform the denoising step, or will chosing "do not overwrite" automatically update the pre-existing files? From reading other posts it seems that most changes in the setup portion require to overwrite pre-existing results?

Thanks a lot!
Joe