The tricky part, as I personally see it, is that you nibble away at the money forever or actually still have an enormously high amount in the pot after the fixed interest rate period, which is then again invested with an unknown rate.
Unfortunately, I do not know exactly what this clause means, as I quickly moved away from it due to the 1% repayment and personally did not deal with it any further. Possibly, it could be related to an interest payment suspension in the first 1-2 years. But that is just an assumption. However, the experts might know about it.
Also interesting regarding the point of special repayments or complete repayment in the [Bayerischen Zinsverbilligungsprogramm] is that this is only possible with inclusion of a prepayment penalty.
I also come from Bavaria and for me personally this is no longer an option. To be eligible for funding, you also have to meet certain criteria in the house planning, e.g. m², as well as income limits, etc.
Best regards, Andreas