Seed saving question.

I read somewhere that for climbing french bean, you should select a strong plant and keep this one un-harvested when wanting to save seed for the next season. Can anyone inform me if this has to be the case, as I would only require enough pods for a handful of seed beans.

Seems unnecessarily restrictive to me as long as you stop harvesting one plant in time for seeds to form I can’t see a problem with harvesting early in the season. Best to select just one plant to set seed as it will inhibit formation of new beans and you don’t want any more than one plant to stop producing.

I would better leave couple of pods from each plant which will give good mix of seeds rather than seeds from one plant.
And alos leave them from the first set if the weather turns horrible you still have mature pods/seeds