Originally Posted by cactuspete
"Mechanically", what's the difference between a walk-in and an SPG instant award?
An Instant Award is hotel-originated exclusively. A Preferred (free) Night Award is one you order online at spg.com or from the Customer Contact Center. Mechanically speaking, an Instant Award has its order number originating from the property and a Preferred (free) Night Award has its order number originating from the database.
And, ne'er the twain shall meet.

Why? Hotels are expressly forbidden from ordering Preferred (free) Night Awards and the Customer Contact Center nor the web site are enabled to issue an Instant Award.
Sincerely,
William R. Sanders
Customer Service Coordinator
Starwood Preferred Services
[email protected]