Giving long and stalwart service, Donald and Douglas eventually became 57646 and 57647 on the Scottish Region of British Railways. In 1959, Sir Topham Hatt needed a goods engine and by his request, BR transferred 57646 (Donald) to Sodor. Such a demanding work-load has begun to tax them, however, and in 1993 the Fat Controller borrowed a navy saddletank named Wilbert from the Dean Forest Railway to deputize for them on the Arlesburgh branch, with the intention of at some point obtaining another engine of Wilbert's class to permanently fill that role.