Two weeks ago Starwood Preferred Guest added Korean Air as a transfer partner. That’s fantastic because Korean has some of the best redemptions in first class (amazing availability), to Hawaii (cheap awards on Alaska, Delta, and Hawaiian), and for business class to Europe (40,000 miles each way with fuel surcharges).
I tested a one point transfer from Starwood to Korean (no minimum transfer is a benefit of being a Starwood Platinum): a Wednesday afternoon transfer appeared the following Sunday night/Monday morning.
That same Monday when I found the points in my account I made another points transfer, looking for another data point for when points would post.