Do I have to spell it out? Really? But as it seems that you've failed to detect the intent, I'll try.
First, a set of statistics have come out that show the disabled have suffered particularly as a result of Covid, quite possibly for precisely the reasons given by
@Bertie the bus, but without being disaggregated. That has put the government on the back foot over who are vulnerable
Second, a high profile relative has gone public about how worried she is about her disabled sister, and the government have decided that the politics of facing down this group of relatively more vulnerable people are worse than sticking rigorously to the original plan.
Personally, my hunch is that it fixes a misjudgement in the original plan and is a reasonable adaptation, but then I've been around enough projects where the project manager has stuck rigidly to the original plan and failed dismally to have some respect for those who tune their plans.
Indeed - when I saw the report, I thought that "disabled" must have been being used in a very broad sense of the word, far more so than is associated with normal usage.