To be honest this is already how it is. Not sure if its in the rules, will check later, but I will not add any additional rules. The special day rule list does have to be looked through, but as far as I am aware, it is last man standing and as you pointed out, not last team standing. So yes, it is not allowed.
On most special days camping is not allowed either, that depends on the special day and which team can/cannot camp etc.
This ain't new tho, but thanks for raising the question