This is independant of encryption because I'm seeing it on WPA2 and Open SSIDs.
I discovered that I can recreate the issue at-will. Once connected to a network, WPA2 in this example, and then connect to my open SSID, the connection icon just spins. While it's spinning (stalled), I can tap the blue icon to see details about the network connection, and it shows I have an IP address. The MAC shows that it's associated to an AP, but I can't find that IP address in the user table and it's not pingable.
auth-tracebuf only shows:
Oct 29 12:24:30 mac-auth-req
Oct 29 12:24:30 mac-auth-fail
Oct 29 12:24:30 station-up
Oct 29 12:24:30 station-data-ready
An auth-tracebuf from a connection that doesn't stall out looks identical.
I compared a healthy connection user-debug to one that stalls out, and the two look similar up till this point:
Oct 29 12:25:36 :524124: <DBUG> |authmgr| dot1x_supplicant_up(): MAC:a4:d1:d2:xx:xx:xx, pmkid_present:False, pmkid:N/A
The stalled iPad, doesn't log any further, but the healthy connection continues to log more.
If you don't have any thoughts on the matter I'll open up a TAC case.