This comes up on occasion and was something I do not recall seeing in the past. I know some have the Chippie Top-Up cards and will transfer funds to their SXM phone to keep the number active. It appears Chippie now offers the option to add funds via their website. The minimum is $10 so this will not work for those who add $1 every 60 days but is a good alternative to add funds when on the island without making a stop to do so.
CHIPPIE Top-Up
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