@Sam *****
that is not correct, you're confusing types of ENTRY
You get in on a 45 day visa exempt entry stamp by air OR land, and border running is just where you go out and back in to get a NEW exempt entry stamp
She's on a 45 day stamp now, she can extend that by 30 days at the immigration office, then she can exit/re-enter the country to get a new 45 day visa exempt entry and get a 30 day extension on that.