In message , at
21:05:26 on Fri, 14 Dec 2018, Robin remarked:

the phone and postal services for the Dart Charge seem quaint and
indulgent compared with the toll roads in eg Sydney where it's
electronic or else - including for visitors in hire cars.

The postal service is only for pre-pay, and needs 10days notice. I'd
characterise it more as applying for a season ticket by post (even if
it's only a one-trip season being paid for).

I wonder if it's mainly for institutional vehicles, where arrangements
for reimbursing drivers small amounts of money are either non-existent
or very clumsy, and they don't want to have a system for drivers to
report each trip as it happens, and the finance department pay the
charge from central funds rapidly enough.
--
Roland Perry