As Wiley see it, the agreement “aims to support and accelerate open access publishing in the UK and is the most extensive UK-based transitional agreement, covering 138 Jisc member institutions. If you are based at a participating institution, you can now also browse and read the entire Wiley portfolio of journals available on Wiley Online Library.”
To publish without having to pay additional Article Publication Charges (APCs), the corresponding author must be from an eligible institution and the article must have been accepted on or after 2 March 2020. To find out more and see whether you are eligible to have your publishing fees covered, go to WileyAuthors.com/Jisc
And note that Wiley has agreements covering open access publishing fees for researchers in a number of countries.