Go to Amazon and buy the sim cards now the when you are ready activate one of them. This is what I did and here is what I bought. You can activate the service online with the sim and the call the porting department to port your number over the temporary number.
(2 Pack) Authentic AT&T ATT SIM Card Micro/Nano/Standard GSM 4G/3G/2G LTE Prepaid/Postpaid Starter Kit Unactivated Talk Text Data & Hotspot (+ Free Tray Removal Remover Eject Pin Key Tool) https://www.amazon.com/dp/B07P98F3YN/ref=cm_sw_r_em_apa_fabc_6FJPMYG3FNZ0C12G77H1?_encoding=UTF8&psc=1
Another Amazon 2-Pack option for future spelunkers is this one (which I'm using right now): https://www.amazon.com/gp/product/B07P98F3YN/
Both of those items go in and out of being available with Prime shipping, sadly, so the more known-good options the merrier, right? :)
Do you think something like this would work ?
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or this
Would something like this work ?
its is unactivated
I am not in the US and I dont have a ATT SIM. Do you think it will work if I buy a ATT from amazon and insert it and try to update it ? Something like this,
I will still be located outside the United States though