Update:
While going through my St. Maarten items, I realized I have a Chippie reloadable top up card that I got at the same time I purchased my sim card. So I went back to the site ruralcarrier linked (which I also have bookmarked on my phone), added $1.00 and now it says my number is extended into May. Not sure why it was not extended when I added funds directly through Flow/Chippie but apparently you have to do it on that website for it to show the phone number extended. So I assume all is good. I will find out in May.
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