The inflation stuff is a bit exaggerated.
Imports account for about a quarter of the British economy. Assuming the pound settles about 15% lower, then on the face of it, that raises prices of imported goods by 15%. But all of those increases won't automatically be passed on to consumers. Competition will see to that. If 8% is passed on, then the price of 25% of the economies goods will rise by 8%. Which represents an overall price increase of 2%.
So there will be an inflation blip of 2%. Since we're in a deflationary economic climate, it's likely to remain a one off event, and work it's way out of the economy quickly.
If everything else in the economy stays the same, including average wages, the average standard of living in Britain will fall 2% - due to a 2% rise in prices with no accompanying rise in wages, or, more technically, a worsening in Britain's terms of trade.
But the increase in the price of imports has other effects. There will be import substitution. Imports will fall over time. More importantly, British exports will get a tremendous fillip from a 15% price drop in world markets. Exports are likely to rise dramatically. Employment will rise. Increased competition for labour will cause wages to rise. It may well be that these positive effects will far outweigh the negative impact of the temporary jump in inflation.