"I am not sure where they get the £571.89 figure for care in my area."
That figure is the current LA estimate for care costs in an average home, hotel cost are estimated separately and are subject to a £12k annual cap. All caps are based on LA tariffs not actual care home fees. When it's up and running LAs can assess individual homes for both care and hotel costs.
EDIT
In my area there was nothing under £700/Wk two years ago so I reckon it will be £800 now
LA rates attached, these are care plus hotel as the care act is not in force yet.
Note that the charge in LA homes is more than their tariff!!!!!