Steve Dulieu wrote:

A further bulletin has set out the procedure for cards that have been
disabled...

"Customers who present disabled cards should be referred to the ticket
office. If the ticket office is closed or the queue very long then
customers with disabled cards should be permitted to travel and
invited to visit the ticket office at their destination if possible.
Presented cards should be checked via the TOM to see if it can be
read, if it can then follow normal procedure.
If a card cannot be read, then the normal failed card procedure
should be used.
Where a customer advises that the disabled card held either less than
£10 of PAYG value or any weekly travelcard then a replacement can be
issued immediately with no further checks necessary. The amount or
remaining days of the weekly indicated by the customer should be
loaded on the card. If the customer advises that the card held a higher
PAYG value than
£10 or a longer period travel card, you should call the CSC on auto
XXXX to validate their details prior to issue. If you cannot get
through, advise the customer that they can travel using their oyster
card for visual inspection only and should return to the ticket
office later. If the card is of a type that cannot be replaced at a ticket
office -
eg a freedom pass - then the customer should be advised to follow the
usual replacement procedure. Freedom pass holders should be advised
to contact the council of issue. Child photocard holders should apply
for a replacement by using the number on the back of the card."

Apparently extra supplies of oyster blanks and gateline passes are
being distributed to busy stations, as well as RCIs being deployed at
key locations to provide support.
The same bulletin also says that customers who were within the system
before 09:30 "may" have been charged a maximum fare on exit. It says
that this will be addressed automatically via gatelines on Tuesday
morning.
Hope this goes some way towards helping people understand what's
going on.

It does indeed, Steve. Thanks very much. Pity that TfL don't seem to feel
the need to give any information at all on their website.
--
Richard J.
(to email me, swap 'uk' and 'yon' in address)