Flew the PDX SEA shuttle yesterday, at 2PM. It was a 737, and all middle seats were blocked from what I could tell, I was in 9F and could not see fully behind me, but from at least row 11 forward it was middles blocked and FC at 50%. Not looking forward to my SEA AUS work trip next week, only 4 seats available, so it looks like that is being capped at 50% as well.