Hi,
Everything depends on the fact what you ordered.
If you ordered part MC9S12XEP100MAG then you can receive any device from the mask set point of view. All XEP devices are automotive qualified but devices with prefix S9S12 have the mask set included into a part number.
So, it does not matter whether you ordered MC9S12XEP100MAG (undefined mask set) and you received S9S12XEP100W1MAG (exact mask set).
The only you need to know is that W1 is a mask set 1N35H to check a correct errata list.
On the other site. If you ordered S912XEP100W1MAGB and you received set of devices MC9S12XEP100MAG with mask set 1N35H printed on the device then it is the same device. However, if you ordered different mask set and mask set is really important from any reason then you should contact your distributor.
Finally, I explained all depenences from technical point of view (We are the Technical Support). I am sorry, I am not able to answer from delivery and package point of view. In this case you have to contact your distributor or department which sent the package.
I hope I explained it clearly.
Best regards,
Ladislav