Update
Look very carefully at the information Valve have provided you…
Having been in contact with Parcelforce they claim that only one carton was assigned to that tracking number, checking my steam account history shows both SD and dock assigned to the one GLS parcel number and the associated Parcelforce tracking number which arrived this morning.
However clicking through the SD link in the “we’re preparing your items to ship” email does actually show a separate set of GLS / Parcelforce numbers which haven’t made it out of GLS in the Netherlands even though they were in the system two days before the now delivered package that just contains my dock.
Not sure if it will show up randomly today without being able to be tracked (as others have reported) or if I’ve just got to wait.
In the same boat here, ordered and paid two weeks ago but the package just made it 20km down the road on the 21st from CEVA logistics to GLS and then vanished.