BREAKING The OBR says it informed Rachel Reeves as far back as ***September 17*** that the downgrade in productivity forecasts was offset by 'increases in real wages and inflation'. The deficit was in fact just £2.5billion By October 31 that deficit had turned into net positive of £4.2billion. That basic forecast did not change from that point So from what the OBR is saying it looks like Rachel Reeves and the Treasury were briefing ahead of the Budget that there was a £20billion black hole in the public finances that didn't actually exist The £30billion worth of tax rises in the Budget are predominantly a consequence of her decisions to increase public spending, particularly on welfare, and have £21.7billion worth of headroom As @Peston @PippaCrerar @hzeffman have all pointed out, it makes the Budget build up - and the narrative that big tax rises were coming because of a deterioration in the public finances - look frankly surreal in hindsight