D9015 entered service with BR on October 13th 1961, and on the same day was named at Doncaster Works after the 1952 winner of the Derby, St Ledger and Eclipse stakes. Like Alycidon, it became a member of the legendary Finsbury Park stud of 'racehorses' until that depot’s closure. In May 1980, Tulyar represented the class at the Rocket 150 celebrations at Rainhill and plaques to commemorate this honour were subsequently presented to the DPS and are carried on its route indicator panels.

After withdrawal by BR, Tulyar was bought for preservation by Peter Sansom and moved to the Midland Railway Centre. In 1986, the loco was then sold to the DPS, the loco remaining at the MRC. Since this date, Tulyar has toured the country, visiting a host of open days and other preserved railways, including the Severn Valley, North Yorkshire Moors, Mid Hants, Keighley & Worth Valley and Llangollen.

Following its appearance at the DPS ’3 Deltics’ event at the East Lancs Railway in March 1997, 55015 returned to the Midland Railway Centre and was withdrawn from traffic the following month to enable a major body overhaul to be undertaken. Some 27 years later and an incredible rebuild including new bodyskin, replacement of miles of wiring, and overhaul of many equipments, the Deltic, now in original livery and number, Tulyar was started up on 30 July 2024, a momentous occasion.