I have exited PRC, but did not complet any exit process before laving. I was on a Z Visa

Hi, your Z has single entry, right? then it has been used up. You need to apply for a new Z visa with documents sent from your new employer such as work permit and invitation letter.

Thank you for your kind reply. However,
Upon entry to PRC,I underwent medicals and subsequently, I was granted a work/residence permit, and was rgistered with local police.

I need to know whether, since I have now exited the country, and propose to work for a different employer in PRC, will I need to make a NEW Z application in London, or will there be a problem because my previous Residence permit is STILL in date from my previous employer who has not cancelled this, and does not assist me despite writing to them?

I understand that I must make a new application for a single entry Z, but will the Chinese embassy quibble my previous Residency and permit for work since its still in date for travel, or will this be canclled once a new Z is issued, and I go through the process agin in PRC? Regards and thank you

I am afraid not, a release letter stamped by your former company is required and they should cancel your old work permit first in order to get a new one by your new employer, then you can apply for a new Z visa.