Class WFBY was a short lived container conversion of old WFDF and WFDY (originally WF) class wagons built in the 1960s.

1990	WFDF 30008, 30009, 30043, 30044, 30046, 30080, 30081, 30085, 30093, 30103, 30114 to WFBY WFDY 30048, 30083 to WFBY
1996	WFBY 30008, 30009, 30043, 30044, 30046, 30048, 30080, 30081, 30083, 30093, 30103, 30114 written off
However, three of this class must have been written back as container wagons as 30009 was listed as AQDX in 2010 and both 30048 and 30080 were listed as AQGY. There is a photo of 30080 as an AQGY here.