Just pray that you never have to exercise one. LOML is taking over her mothers financial affairs as she has early-onset.
Bottom line....she has spent days and days and days wading her way through umpteen companies that have zero concept of what Lasting Power of Attorney actually means. The worst culprit is effing bloody Santander. Their Power of Attorney team move the goalposts daily. I've told LOML to stop messing about, send them a letter detailing how much she is going to invoice them for her time wasted.
Even when they do, companies manage to cock things up. For example, BT managed to set her up an account online to manage her mothers' account. Only they managed to combine her old details from our last house with her mother's details, then filled in security questions and answers but failed to either let LOML know or log the even within ther systems. That took four days to sort out and umpteen phone calls.
So...just pray you never have to get involved