I'm sailing on the Symphony on May 7th. I got my balcony officially assigned exactly 30 days out, when the cruise documents were available. However, right after we did the online check in on the app at 45 days out, our set sail pass showed our room number as the last 4 digits of the bar code number. We were able to see the barcode number after we added our set sail passes to our iphone apple wallet.
It ended up being correct!