Richard J. wrote:
I see that Network Rail are imposing a blockade at Gunnersbury from
Saturday 1st to Sunday 9th April inclusive in order to relay the
junction. Silverlink Metro and LU District Line services from
Richmond to South Acton/Turnham Green will replaced by buses for the
whole 9 days.

Why does it take 9 days to replace a double-track junction?

Although the earlier posts in this thread established that there were
some drainage problems, and limited clearance under the road bridge (not
exactly unknown on the District Line), nobody could offer an explanation
of why it will take 9 days.

I'm reposting this, and crossposting to uk.railway, and would
particularly like a response to the following question:

Have there been any recent replacements of similar junctions that have
been done over a weekend, for example?

--
Richard J.
(to e-mail me, swap uk and yon in address)