Can confirm that Enrollment on Arrival is available at ORD, apparently it reopened on Sunday.

Since you applied for your renewal before expiration date, you have up to six months from expiration date to complete the process.

Next time mark your calendar to renew at T-364.

The booths are numbered and some are labeled at times, and 58 sounds like the lane that is for or very close to the lane most commonly used for MPC. For MPC there is a pass line in the middle between the lanes for say visa holders and the lanes for APC users, although more times than not most of the booths aren’t open. I would go into the MPC line and then cut over to 58 (if it’s open) or tell the contractors while standing waiting to be directed to a particular booth.

FWIW, MPC receipts can be processed at ORD T5 even by non-MPC-designated booths. They will then hand you a MPC rectangular card to show at the customs exit — and those cards can be a minor issue — when they want receipts to exit the baggage area and customs.

In your kind of situation, I would set myself up for MPC use on the 55-58 booth area and then ask to do enrollment on arrival and see what they suggest. Note that the published hours for enrollment on arrival at ORD haven’t been all that great and that even MPC booth is often not staffed — but MPC still works even at times when enrollment on arrival didn’t.