Dual-citizen applying for Tier 4 visa

[voiles]

Hello all. This is my first post and I will be extremely grateful if there might be advice.

I am a dual US/Taiwanese citizen. And because I have spent three years working in Germany, I obtained a German residence permit. What happened is that I have applied for a UK university when in Germany (an EU country) and received the unconditional acceptance letter from the University a week before classes started (too late for a proper Tier 4). Also I expected, that while the Masters program is one year long, it travels all around Europe, and I would therefore not be spending more than six months overall in the UK. Thus I chose to enter as a student visitor.

However, upon entering the University, they advised me to seek out a proper Tier 4 visa, and I understand that there will be exams and thesis defense (each lasting a week at most) beyond the current 'stay' period of my student visitor clearance, and might affect the attainment of my degree. They gave me a CAS number and I flied back to Germany, only to learn that I had to surrender my passport for a couple of weeks for the visa. As I cannot miss 4 weeks of classes, I flied back to the UK on the same visitor's visa and planned to apply for it over December in Taiwan instead.

When I flied back I explained the situation to the border officer and he said something to the effect that if I apply for another visa it will be rejected. I said I am in the process of applying for a proper Tier 4.

The problem is, I am a dual citizen. I have an 'official' permanent residence in Taiwan but I actually don't spend a lot of time there. The most straightforward way will be to apply in Taiwan over the break and send in both passports, and visa decision in Taiwan is very fast. On the other hand, if I were to submit my application in Germany instead, either I will be stuck in Germany the whole period (thus unable to visit my family over the break), or if I take the risk and go home on a Taiwanese passport which might post additional problems with travels in the schongen countries.

It is true that I much prefer going the Taiwan route than the German one but I want to know if there will be some serious problems that I have not yet considered. Please advise.