Guidance needed About PMS and PCS

[Yousaf Khan Tareen]

Hi and Assalama-o-laikum. I hope everybody is doing good.
I've been wondering that whether PMS is the same PCS, just changed its name or its quite differenet from PCS.
PCS = Provincial civil services
PMS = Provincial management services.
If PMS is the same "PCS" then it doesn't give any sense of changing the name from PCS to PMS, why name change then?

Some of the sources that I consulted had said that PMS is conducted on yearly basis like Css comparatively to PCS which is conducted on the basis of vacancies present. Moreover, I have heard that PMS is just conducted in Punjab & Khyber Pakhtunkhwa not in Balochistan and Sindh.