None at all.
Undocumented losses will never be reimbursed (basically, what you never had, you never lost).
In addition, giffgaff's T&C's specifically exclude business use.
' @ballantyne23 here is the giffgaff official announcement about the Outage and refunds please read
Hi I was unable to work on Thursday as the network was down as I am an uber driver so lost a full days earnings as I rely on the mobile data Am I entitled to any reimbursement? Thanks
Given that giffgaff don’t guarantee service and are not liable for consequential loss if service is not available @ballantyne23 then based on what you say giffhaff is not for you.
If having a service that's guaranteed and so responsible for compensating you if it is unavailable, is important to you then you need to consider moving to another (non-O2) provider on contract and keeping your giffgaff sim as a back up in case your other provider suffer problems.
It works well as a back up as you don’t have to buy a bundle every month - just as and when.
And as long as you keep the sim active by doing at least one of the following at least once every 6 months - make one call, send one text, access the internet for a couple of minutes or add some new money (either credit or a goodybag) - it isn’t that expensive to keep going for years.