I've only ever handed immigration my passport so they never see the ticket of the flight in - so how would they know which class you flew in on? Mind you, I have a retirement visa and follow all the rules, so I have never had dramas entering or leaving.
Hubby and I have a joint account and we are both on nonO retirement. We have to both keep 800K baht (so 1.6m total) but no dramas with immigration over that.
When was the last time you lived in Aus? Cost of living there also rose dramatically since the pandemic. Hubby and I moved over here in 2023 because costs in Aus almost tripled. Costs here in Thailand are no where near the 80% mark and are closer to the 30-40% mark, unless of course you want to live exactly like you did in Aus in a large modern house with pool - and only eat western foods. We live comfortably here, eat well and enjoy life for far less than we did in Australia.
They ask a few questions about your personal situation and determine eligibility. As long as you worked a job which paid into SSA at least 10 years, you are eligible so that's not something to stress over. Make sure your phone is charged and next to you to ensure you don't miss the call as rescheduling could mean an additional 3 months because Manilla is slow. They won't ask anything you don't know, nothing you really have to prepare.
I would however make sure prior to this suggest you set up a my social security account and check your earnings page to ensure all the jobs you had actually are there and that the funds paid are as correct as they can be, as that's the information they use to determine the amount you receive.
While I realise that - it is the worst case scenerio for the op. In other words - while it is highly unlikely - even if it did happen she would have a less costly exercise fixing it here than there.
Worse case scenerio, is if they treat her as an Aussie tourist - she has 60 days on a visitor exemption to update her thai passport within Thailand - do a quick border bounce and return on the thai passport. It'd be far cheaper to border bounce over to Vietnam (you'd need a reentry of course) than to travel from Brissie to Sydney.
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