Is this an all-time low for Scottish Labour?

As we all know, an individual Scottish subsample from a GB-wide voting intention poll is rarely of much use, except as a straw in the wind when there's absolutely nothing else on offer.  But the latest subsample from YouGov is worth mentioning for the sheer comedy value alone.

SNP 38%, Conservatives 22%, Liberal Democrats 19%, Labour 11%, Greens 5%, UKIP 2%, Brexit Party 1%

I must admit that I don't keep track of all-time highs and lows in subsamples, but I find it hard to believe that Labour have ever been much lower than 11% in a YouGov subsample.  OK, we all know that they aren't really on 11% (and the Lib Dems certainly aren't really on 19%), but nevertheless YouGov's subsamples tend to be a little more reliable and less volatile than those from other firms, so it's reasonable to suppose that Scottish Labour must be doing pretty badly for this to even be possible.

What makes the timing strange is that there are signs that Labour may have steadied the ship at GB level - the newest Survation poll gives them a three point boost and has them back in the lead, while both Opinium and YouGov show a reduced Tory lead, albeit due to a falling Tory vote rather than a rising Labour vote.  In YouGov's case what seems to have happened is that the Tories have suddenly lost a significant slice of support to UKIP and Nigel Farage's new Brexit Party, probably due to the (dubious) perception that Brexit is now at risk after last week's Commons votes.  Meanwhile, memories of the Independent Group split are fading with no further defections having taken place for weeks - which is very good news for both Labour and the Lib Dems, who had both taken a hit in polls conducted in the immediate aftermath of the breakaway.

There are suggestions that Jeremy Corbyn may be contemplating another no confidence vote in the government if the Brexit deal is voted down for a third time.  The only way the government can conceivably lose a confidence vote at this stage is if a smattering of Tory MPs take the nuclear option and risk their own careers by voting with the opposition.  Presumably the Labour whips already know whether there is the remotest prospect of that happening, but even if there isn't, it may still be good tactics to table a no confidence motion because it will put the Independent Group (and possibly the Lib Dems) on the spot.  It's one thing for former Labour MPs to talk about propping up a Tory government by abstaining, but actually being seen to do it for real is another matter.  If the Independent Group start to be seen as the Tories' little helpers, it could well deter wavering Labour MPs from defecting.