Work permit- What's about,if we change our company (Istanbul)

Hi everyone,

My question is about the application for a new work permit by changing my company.

As you may know, a work permit is linked to a company.
Having a work and resident permit valids for 2 years, doesn't mean that you can change company freely within this period.
A new application, must be done.

For my part, I'm currenly working in Istanbul and my mission is being finished soon. I would like to stay here and consequently I will apply for a new company.

Thus, I would like to know if someone has already faced a such situation.

Some people told me that the process should be carried out from the initial step,
Others, told me that, as we have already a SGK record, the process takes less time.

I'm calling your experience about this ?

Thank your for your feedback,
Samuel.