HMRC have issued a brief notice describing the new refund schemes introduced in the budget for certain charities, including hospices. See https://www.gov.uk/government/publications/vat-notice-1001-vat-refund-scheme-for-certain-charities/vat-notice-1001-vat-refund-scheme-for-certain-charities

It doesn’t go into very much detail. In part I suspect because some points are still being discussed.