Could you share with us the solution you found? I have the same issue! I want to start to work on upwork, but I don't know what is the best way to do it! Do you invoice Upwork or the client? I have heard that in the meantime, upwork has changed its billing mode, writes the name of the freelancer, but you pay money to upwork(in case you want to hire a freelancer). In case you want to work on upwork, the invoice contains client name?