Got it. I wasn't logged in, was just checking from the home page where you don't get those options. I'll have a chat with her as due to her age (>70) she may not want to take a bus/flight to Cambodia/Laos/Malaysia. We'll see.
An interesting point about booking flights though. If I book a 90 day return flight on a 60 day TR I suppose technically the airline could refuse boarding even though it is very likely she'd get the extra 30 days. I wonder how often that happens? Pretty sure she's done this in the past without any issues.