Money Moral Dilemma: Should I tell HR that I'm now able to approve my own work expenses?

philip57

Be positive while protecting yourself. Notify HR and your stand-in boss in writing that you will continue to authorise your own expenses until more appropriate arrangements are made, at which time you would like the "new approver" to review and sign off what you have already approved for yourself.
Do not withdraw from any of your roles or work - that will just cause problems for your colleagues and customers.