hi china, sorry its a bit late, bin heads down in the markets

This kind of thing is not specifically covered by the rules, tho there is a provision for going optional if affected by a BF upgrade. I guess it would require all settlers to agree on doing that, but TBH I didn't see much complaining so a sleeping dogs situation IMO, not that any of our esteemed napsters are dogs (tho some have occasionally been caught napping! )