I made the mistake of updating to this version before testing and I totally disrupted my network ops.
I'm not sure what was going on, but I was perfectly running on 4221 and when I upgraded to 4452 and rebooted, the iSCSI service did not appear to start. I had to downgrade back to 4221 for things to work again.
The release notes don't indicate any significant changes. Was I missing something?