Z visa , change the workplace, before contract is finished

I have Z type and working in the same province since 3 years, now i found a job in the new province. My working visa will be expired at 18 February and my „Foreigner expert certification „ (red Book) will be expired at 24 February, my contract will be finished at 24 February too.
I can only go to the new province around 25 January (24 days before my Z type is expired) and the Chinese new year is at 8 February and all office is closed from 8 to 13 February.
My new Employer in the new province ask me ( my current employer) to cancel my „Foreigner expert certification„ (red Book) now, before my contract is finished, because i want to start to apply for the new „Foreigner expert certification „ (red Book) ,regarding this fact:

1. if now my current employer cancel my „Foreigner expert certification„ , before my contract is finished , my Z type and my contract will be canceled too? I will lose all my bonus at the end my contract?

2. I will be able do medical examination earliest around 25 January, can my new employer start the procedure without it?

3. Is it possible to extend my working Z type after 18 February for one month (not as Visitor Business visa) to have eng time to apply for new „Foreigner expert certification „ (red Book) and new Z type?

4. According the facts: My Z type expired 18 February, arriving at the new province 25 January, new years holiday, what is the best way to extend my working Z type and my red book, without to extend my visa for one month?