I am a non EU national currently working in Germany and in my 3rd month here. I am qualified to apply for EU Blue card but I have not started the process yet. Due to certain personal circumstances which I did not expect, I am looking to change jobs within Germany. I have not yet started to look due to the fact that I am still on National Visa. I was wondering what kind of complications I would face if I want to switch jobs within Germany.
So, do I understand it correctly if you arrived to Germany recently, work for a company, which is specified in your national visa, and now want to change the job?
Then just look for another job, sign the contract with them and then go with this new contract to the Ausländerbehörde to explain them your situation.
Hopefully, there will be no complications. However, for the new job, if the salary will not be enough to apply for a Blue Card (52,000 Euro per year brutto) you may need to be checked via a job center, which may take a while (3+ weeks).
I would recommend you to negotiate a starting date for your new contract, so that you have at least 2 months in advance (before staring a new job) to clarify the issue with the Ausländerbehörde.
P.S. I'm not a lawyer.