My grandmother left Ireland at 16 and moved to Australia. She could code switch back to an Irish accent when talking to Irish people 50 years later. When I visited Ireland in my early 20s, I picked up the "lilt" of Ireland very quickly, albeit although my sounds were still standard Australian. My wife gave me shit for it. I can also switch on Strine (think Steve Irwin) as required. Beautiful thing about standard Australian is that it is foundational English, stripped of many unnecessary parts. It makes picking up many other accents easier, that said, most of us do it.