Wirelessly posted (BlackBerry8530/5.0.0.601 Profile/MIDP-2.1 Configuration/CLDC-1.1 VendorID/417)
"Upgrading is not supposed to be allowed but I managed it once."
Is upgrading not allowed because it's a weekly special ticket? On other tickets, if a sleeper is available, it is supposed to be available for purchase on board at the lowest-priced fare bucket.