Much less scary than the employment balance of the PMI survey. With pay growth at 5-6% yoy and NICs adding 2ppt to total labour cost hard to see any other result than inflation

Agreed. That demand for primary issuance is strong by historical standards. Chart = monthly average of bid-to-cover ratios on gilts.

Pay growth has slowed dramatically for the top half of earners, making the potential inflationary impact less of a concern. But the tax adds to large increases in minimum wages for low-paid workers, meaning total labour costs will continue to increase substantially in some sectors.

The good news is that the UK has a relatively low tax burden on labour at present, so it is unlikely to be overly damaging for incentives.

At the margin, yes. Higher taxation of labour goes along with lower hours worked. That's because it incentivises firms to reduce labour inputs, or if passed on to lower wages or higher prices, individuals to work less.