One morning within the last two weeks, there was an announcement at Bank to the effect of:
"Customers are advised to board this train as there is another having difficulty approaching us."
... which was all very well for anyone heading towards Lewisham, but seemed to be useless for anyone needing the King George V service as it implied that we would have to wait somewhere anyway for either the problem train or the one behind it, unless (which was not said) some trains were being turned at Shadwell.
In the end it wasn't too long before a KGV train arrived.
However, when I tried to use the "Contact us" form on the web, the mail bounced.
It would have been helpful to know what was going on - though fortunately there was no real problem.