[mothered]

I intend on having it picked up on a Friday afternoon, so there is atleast a whole weekend for it to sublimate. However Im uncertain of when they will weight the parcel, if at all, thus making it hard to predict how much extra dry ice I should pack to compensate for this window.

It's probably not the best Idea to do this on a Friday- quite difficult to calculate sublimation during storage.

For cost of freight (weight or volume whichever Is the greater) and record keeping purposes, carriers take weights & dimensions of all packages at their depot. As such, when using dry Ice, It's best to have the package delivered to Its destination as quick as possible. This will minimize Inconsistencies In weight from dispatch, to the depot and to the receiver.