The rear uprights are a little different in their effect than the front uprights. Its less about raising roll centers and more about reducing roll couple along with linearizing camber gain.
More can be read here.
https://docs.google.com/document/d/1h10XeCaC56HzIcGyOKKhqgrYcN-rk5cmw9JMQ_gMiwQ/edit?usp=sharing