Keith why don't you read the stuff you posted links to?

The projections there were based on 2008 figures: fact.

We now know (from the very same ONS) that ever since then net immigration has been falling: fact.

You ask whether the immigration is sustainable: look at the age profiles in the same stuff you linked to: we need more immigrants to provide an economy that can support the ageing.

Either that or you will have to start exporting or killing the ageing, or starving them out. You call yourself a physicist? You should be able to work out the arithmetic.

I repeat. If you called the stuff you posted to the most up to date information, then you are a liar.