I would like to know what will happens in the follow senario it is a CMYK job.

I have a colour page. A section of it is covered with a alpha channeled tiff.
I also check the transparent box of the tiff. Will the colour of the page
section that is covered with the tiff be the same as the the page that is not
covered?
I ask because the aplha channel rasterises the image into RGB then back to
CMYK.

Any help would be appreciated.