Taken from https://www.gov.uk/guidance/coronavirus-covid-19-advice-for-tier-2-4-and-5-sponsors?utm_source=4a758c33-7bc2-404e-a091-932976dbfe5e&utm_medium=email&utm_campaign=govuk-notifications&utm_content=immediate on 15 April 2020.
UKVI webpage: Coronavirus (COVID-19): advice for Tier 2, 4 and 5 sponsors (14 April 2020)
Home Office Documents | Economic Migration