Need Advice Regarding University Change on a German Student Visa 🇩🇪

Assalamu Alaikum everyone,

I’m currently in a somewhat complicated situation and would really appreciate advice from people who have experience with changing universities in Germany while holding a Student Visa, especially in cases involving a Private → Public University change.

I received my German Student Visa based on the admission/offer letter from a Private University. My visa will be valid from 18 August, and InshaAllah, I’m planning to travel to Germany during the first week of September. My current Private University’s classes will start on 1 October.

However, in the meantime, I have received an admission/offer letter from a Public University, and I would now like to switch to that university.

The situation is a little complicated because:

\\\* The enrollment deadline for the Public University is 26 August.

\\\* This means I need to complete the enrollment while I am still in Bangladesh.

\\\* The first semester at the Public University will be conducted online.

\\\* My German Student Visa and travel plans, however, were based on the admission from the Private University.

So, I would really appreciate advice on the following questions:

1. What should I do in this situation?

Can I complete my enrollment at the Public University while I am still in Bangladesh and then travel to Germany in the first week of September and inform the Ausländerbehörde about the university change after arriving?

2. Could enrolling at the Public University from Bangladesh cause any problems when entering Germany or during immigration?

3. If the immigration officer asks which university I am enrolled in / which university I will be studying at, should I show my documents from the current Private University, such as the Offer Letter and the documents that were used for my visa application?

4. If I enroll at the Public University before travelling to Germany, can the German authorities or immigration authorities somehow find out that I have changed universities or enrolled at another university?

5. What would be the safest and legally correct procedure in this situation?

Should I:

\\\* enroll in the Public University now and inform the Ausländerbehörde after arriving in Germany

I would especially appreciate responses from anyone who has personally gone through a university change in Germany, particularly a Private → Public University change, or anyone who is familiar with the official procedure.

I want to make sure I handle everything legally and transparently and avoid any issues with immigration, my residence permit, or university enrollment.

Thank you in advance for your advice and experiences. 🙏🇩🇪