I'm waiting to do my COVID-19 training so am doing the 'day job' for the moment. Will I get a letter of introduction so I can travel to and from work for the time being for my day job until I'm pulled over to COVID-19? I'm not able to work from home?

Only people working on COVID-19 or a business critical function has received a letter to enable them to move around for work during the incident.  No one else should need to move around for work purposes as there is no ‘business as usual’ being undertaken.

Once they are deployed to COVID -19 they will receive a letter if they are unable to work from home to undertake the work.