Should Door Trim/Jamb be flush cut with bottom of base for carpet install?
I always hold casing to the same height as the base trim (3/8" or 7/16" is enough--1/2" risks showing a gap with thinner carpets). However, if the casing is already installed, don't bother making cuts now. Carpet layers can easily deal with that situation by tucking against it. It shouldn't be a visual concern.