In article , Clive D. W. Feather
writes
Box junctions. These have criss-cross yellow lines painted on the road
(see Other road markings section). You MUST NOT enter the box until your
exit road or lane is clear. However, you may enter the box and wait when
you want to turn right, and are only stopped from doing so by oncoming
traffic, or by other vehicles waiting to turn right.
-- Highway Code

I'm amazed by those who didn't know this, since it came up as one of the
questions the first time I passed the driving test well over 20 years ago.

It seems to me that this advice is rather naive, because it assumes that
the only impediment to the "car in front of you that's also waiting to
turn right" is the flow of oncoming traffic - which will eventually
stop.

The wording appears to have changed. It *was* something like "... oncoming
traffic going ahead or also turning right". In other words, *one* car can wait
on the box to turn right from each direction, but that's all; the second car in
each queue must wait to enter the box, just as when going straight ahead.

Yes, and some people are assuming that the junction is a cross roads. It
might just as well be a right turn only (from the right turning
vehicle's point of view) which means that being the second vehicle to
enter the box waiting to turn right doesn't actually obstruct anyone.
--
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