RAM is cheap as it is, and he's already gone from a 5950X build (£600+) to a 12600K (£280) so I doubt OP would be too concerned about spending an extra £100.
Although he might not use it now, I would still go for it, if OP really doesn't need that much RAM you could argue that a 12400F would be a better choice.
That's how I see it anyway, you cap your machine at 32GB aswell if you get sticks of 8GB, without getting all new sticks.
