Here's more detail on my background:
• I'm a US citizen living in Berlin, Germany
• I was issued a Blue Card in November 2015 to work as a 'posted employee' for a US company. The Blue Card is valid until November 2019.
• I am in the German private healthcare system (through Allianz)
• I have a lease on an apartment here in Berlin (not temporary housing--a 'regular' rental contract)
• I have more than sufficient savings in the bank to support myself in Berlin for a year or so (in case immigration authorities would like to see that--not sure if relevant, but I've been told it's something they might ask for)
• As for background: before moving to Berlin, I spent 7 years in San Francisco / Silicon Valley working in product management roles for tech companies.
My current job isn't a good fit for me, and I am going to leave it to search for different job here in Berlin. Ideally, I'd like to take one month off in between jobs to complete an intensive German language course.
My specific question: if I leave my current job before I find a new job in order to take time off and take the language course, will I need to forfeit my Blue Card then 'start from scratch' with regard to getting a work and residence permit? Or will I be able to keep the Blue Card then transfer it to a new company once I find a new job?
I'm trying to determine whether it's worth it to wait to find a new job before leaving my current job so that I can keep my Blue Card.
If handling the situation is complicated, I'll likely end up working with a lawyer, but I am doing some independent research first to see whether hiring a lawyer is necessary.