You can all keep throttles indefinitely, but only operational when you are turning the pedals as well.
However, considering the 400 million people of the other EU countries all manage without throttles when they ride e-bikes, and they do much, much more of that than the British do, I do wonder at the apparent competence levels in Britain.
Of course the truth is that you can be just as competent, but as Biged says, you just want your cake and eat it, but there's no chance of that.
Be content with pedelecs or buy a moped, getting your CBT and test pass where necessary.
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