I just checked with TireRack and it's NOT a good time to go shopping for winter tires. The stock is very limited due to the time of year. Also, snow tires are not governed by the same rules as summer tires, so we will be able to use lower speed rated tires than their current listing.
Right now, the only winter option for the 330i SP is a Continental tire that is "VR" rated. VR means 130+ mph.
Put your checkbooks away until later in the year!
John