AlpineSIM does not provide any truly unlimited high‑speed data plan for Montserrat. The plans labelled “Unlimited” give a fixed daily allowance, such as 500MB/day for 1 day, up to 5GB/day for 1 day, and after the limit is reached the speed is reduced to the carrier’s reduced speed tier. Because the high‑speed data is capped, these plans are not unlimited in the strict sense.
If you need a larger amount of data, AlpineSIM offers fixed‑data options that can be more cost‑effective for long‑term use. For example, a 20GB plan valid for 30 days costs $112.91 USD, and a 10GB plan also valid for 30 days costs $61.51 USD. These plans provide a set amount of data with no daily caps and maintain high‑speed connectivity until the allowance is exhausted.