The restriction presumably arises from the introduction of 'A' stock on the
East London line.

This has a somewhat wider loading gauge than normal sub-surface stock, and
is not normally operated east of Aldgate.

"David Splett" wrote in message
...
"Sharon & Gordon Thomson" wrote in
message ...
Has its use always been restricted to one train in one
direction at a time because of tight clearance?

No. This restriction appears to date from approximately the time of the
East
London Line Closure. I can't remember if it was just before, during or
just
after.


Has anyone on the group
travelled it over it?

Yes; last year's East London Explorer railtour, operated by Cravens
Heritage
Trains, ran over it in both directions. I have also seen material which
suggest that football specials from Surrey Quays have taken passengers
over
it; I've no idea what (if) that ceased happening.