Take the 12!
Would be great if you never have to use it, but if it hovers around 12-16 knot the whole time you will be soooo much happier.
the ten is great, but nothing worse than being underpowered for a week knowing you have a 12 sitting at home.
Wind is never dependable.
If you absolutely cant bring em all, I would bring the 12/8 every time over the 10/8. It would be way better to miss having the 10m and ride the whole time, than to miss the 12 and not ride! The 12/8 have good overlap.
Since you’ve already packed it a couple times, it’s probably best just to take it.
I hope you get 8m wind the whole time and come back thinking I’m a fool with this advice!