Originally Posted by
lowfareair
It's almost certainly to monetize it for non-elites - "you're in a middle, an aisle became available but it is a preferred seat. That will be $32 if you want to switch."
If it wasn't for the monetization, I could see an elite benefit being a 10-15 minute delay on these notifications to non-elites, but I'd expect they'd think it would lose too much money.
Yeah - one is to create upsells to non-elites who aren't eligible for seats that become available.
The other would be down the road to make it a paid subscription service - for $5 do you want to receive alerts about more desirable seats on your upcoming flight? Could be a benefit free to elites.