Yoast and sitemap.xml

Hi All,

I have two questions regarding Yoast:

I have my Robots.txt file pointing to my sitemap like so:
Sitemap: http://www.MYSITE.com/sitemap.xml
Sitemap: http://www.MYSITE.com/post-sitemap.xml
Sitemap: http://www.MYSITE.com/page-sitemap.xml

My question surrounds the fact that yoast now generates the sitemap.xml on the fly, so, when it does how do I know how to point my Robots.txt file to it correctly?

Regards,

Tommy