Yes. My understanding is that they must manage the funds, on your behalf. Meaning that they must establish and maintain (aka re-balance) an asset allocation on your behalf. If they allowed you to trade, they would no longer manage your funds and they would be in a danger zone.
This is also the reason why I am very sceptical about finpension (and I exited all their services accordingly)… With their option to disable re-balancing, they technically violate that principle. I don’t want to do business with companies that ignore and violate laws and regulations…