Actually @Cabra1944 is correct - there is no clarity because few people are reading the small print. "Existing claimants will no longer be assessed under the “4 point” criteria at renewal IS the u-turn" - and it is, assuming this is agreed, for now. The small print on the offered U-turn says that ministers will undertake a review of how PIP is assessed, consulting with disability charities. Knock off those last four words ("consulting" does not mean "agreeing with" or "implementing their ideas or proposals") and you are left with "ministers will decide to change the way that assessments are conducted". It is not a U-turn. It is a mealy-mouthed concession of a temporary nature until they whip their troops into line. I understand that MP's are being told that they will be deselected before the next election if they do not back the government, and will never serve in any ministerial position. Someone I know, elected at the last election, was told that precise thing by Rachel Reeves two days ago. They will still be voting aganist the bill, because they now trust them even less than we do....
Edited - I should have added, remember that changing the way assessments are conducted does not require any legal changes or reference in any form to Parliament. It is an administrative matter.