I had a Galileo Confirmation Number pop up today and figured I'd add my info (as this was the first search result on Google).
My LH flight (booked as UA reward flight) from BOS-FRA was cancelled due to strike.
UA auto-rebooked me on FI (Iceland Air).
I called to confirm rebooking, as it showed up as "waitlist" in UA app, and was given a confirmation number.
When I tried checking-in at FI website, it wouldn't pull up a record.
Went back to UA and searched original itinerary and found "additional confirmation number" listed as "Galileo Confirmation Number: XXXXXX" (same number from phone call).
I can pull up the reservation on viewtrip.com, but it says e-ticket not available - I just see my name/flight times.
I'll head to the airport in a couple hours to check-in at FI desk, since can't do anything online.