Well, I've some bad news for all of us hoping to upgrade our head units to the 2018's:
Dear Mr. XXXXXXX:
Thank you for contacting Subaru of America, Inc.
Unfortunately, the new head units are not able to be retro-fitted into previous models.
Should you have any further questions, please feel free to contact us again.
Sincerely,
Amber Anglin
Subaru of America, Inc.
Customer/Retailer Services Department
1-800-SUBARU3 (1-800-782-2783)
Service Request Number: XXXXXXXXXXX
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I just sent a reply asking if she could post an inquiry to whichever department writes the code if the new head unit's software could be loaded onto the older head units, and suggested that if Subaru could find a way to retroactively add CarPlay/Android Auto functionality to cars that didn't come with it natively, that it'd be a hell of a press coup for Subaru.