Some people who've lived near the NLL for longer than I have are telling
me that some 10 or possibly 15 years ago, the North London Line (or part
of it) was closed *for two years* while the track was upgraded for use
by Regional Eurostars (e.g. to enable them to get from the WLL near
North Pole to the ECML). I've read that lots of money was spent on
infrastructure improvements for Regional Eurostars, in addition to
building the trains themselves, and it seems plausible that this
included some track renewals or other work on the NLL.

But two years' closure? Not only does that seem excessive and unlikely,
but I can find no mention of it in online articles on the NLL. Can
anyone shed any light on the matter, preferably with references, online
or otherwise? If the track was renewed in the '90s, was other work
done at the same time, e.g. on signalling or power supplies?

--
Richard J.
(to email me, swap 'uk' and 'yon' in address)