I'm not sure how ya'll coded research, but I noticed something wierd today.

I had tech 0 propulsion researched to 76% and switched 100% to tech 1 biology. At the next turn, I researched some biology and got the propulsion to level one (despite all research being switched).

I haven't tested it, but if this type of thing happens everytime, it could easily be abused.

it's normal. Once you are higher than 75%, there is a not-so small chance that a scientific breakthrough happens without allocating further funds/RPs so it's intended.