In 1950 JG12151/2/8 were written off followed by 12155 in 1954. The remaining JG class tank wagons (12153/4, 12156/7) were converted to QJG class flat wagons in 1959. Three years later in 1962 numbers QJG12151/2. I suspect that these were not new wagons but the reinstated frames of previously written off JG's with the same numbers. In 1979 the whole QJG class was written off only for four of them to reappear again as JOB class tankers in 1983/4.

QJG12156 enjoying a new life as a JOB class tanker