How did you come to fail to declare this?
Ok. There is a risk either way. That is the truth of the matter.
They may prosecute you even if you don't ask for recalculation. I can see why you would want them to recalculate as this is just plain wrong.
They shouldn't summons just because you ask them to correct an error but we all know the reality of human nature.
I would in your position. The saving is likely to be worth it.
If that annoys them and they start considering a summons then that is a risk. People are like that.
But it would be worth it here.
No but it is the conviction that you want to avoid.
In your position I would ask them to recalculate.
All the best.
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