I use skinbiology lactic acid a few mornings a week, and my CP at night. If I use the SkinBiology Day Cover, will that be too much CP's and is it fine to apply it over the lactic acid cream?

People do this. The two products should work together.

Thank you, Dr. P. So, the Day Cover in the morning and another CP at night won't be too much, or is this something I will just have to play with?

It should be OK. If there is any irritation, then use less product.

Ok. Thank you!