From 2nd November 2020 it will be complusory for solicitors applying for Probate to use the on-line portal. At present only about a third of such applications are made through the portal - so this will be a big change for the profession. Here's a link to the Statutory Instrument if you are interested: https://www.legislation.gov.uk/uksi/2020/1059/pdfs/uksi_20201059_en.pdf