Between 1946 and 1949 eighteen LMS Patriot Class engines were rebuilt with Stanier 2A boiler, cab and tender, though these were largely paper rebuilds, based on the LMS Rebuilt Royal Scot Class. Seven (Nos 5514/21/6/9-31/40) had been rebuilt by the start of 1948 when British Railways inherited them. In March 1948 BR added 40000 to their numbers to number them 45514/21/6/9-31/40. Subsequently, BR rebuilt another 11 of the Patriots, so that the rebuilt engines were (4)5512/14/21–23/25–32/34–36/45. The two original members of the class, and the first ten of the nominal rebuilds, were not rebuilt due to their non-standard parts.
| Year |
Number rebuilt |
Numbers |
| 1946 |
2 |
5521/30 |
| 1947 |
5 |
5514/26/9/31/40 |
| 1948 |
10 |
45512/23/5/7/8/32/4-6/45 |
| 1949 |
1 |
45522 |
| Total |
18 |
|