In message , Nick Cooper
writes

Don't know what alternative arrangements might be made, but there's little
or no chance that the area of suspension will get any smaller. The only
other available reversing facility on the route is at Wood Green, and this
can only be used to reverse from east to west.

So what actually precludes a westbound train running into Wood Green,
reversing (east) into the siding, then out again (west) to the
eastbound platform, before heading back east again?

The points/signals from the sidings can only be set for one route (which
is into the westbound platform).
--
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