I don't think you are wrong to say that, but buses awaiting
deregistration can have been laid up.
If they are not laid up, I dun see why this status should be
reflected. One good example is the Leyland Olympains.
Did you see the LO in AMDEP?
Those await de-reg had their ezlink removed and coinbox
remove
Also there is also a paper pasted " Do Not Deploy "