Claiming backdated PIP for Mental Health Mobility

Hi, I had an assessment and received PIP for daily living ( enhances rate ) due to mental health problems. In 2016. I didn’t receive any mobility component. I did ask for a MC on this at the time in 2916 but was immediately told I was not entitled. I’ve just been reading some articles about various rulings that mean some people with mental health conditions can now claim the mobility component. Also, if eligible will this be backdated? I believe I should have been awarded it as I struggle to go out and struggle with bad anxiety when out. My claim is due to be renewed anytime now as my award runs out in a few months. My question is: Is it worth phoning and asking for or if my claim was looked at again after these court rulings to see if I should have been entitled to the mobility component? I know I am soon to be renewing but if I ask now and they find I am elegible that will mean they owe me money from these last few years after the ruling?

Any advice? Thank you.