Is it not based on your history? I know the suggestions seem to be. If so and it's stored locally it could just be that it's having to start again from scratch?
It used to be very clearly based on history, so every time I restarted my phone I'd get the classic "duck" correction.
Now I couldn't tell you what it's doing, but it doesn't appear to be using history. For instance, the same technical terms get autocorrected again and again.
