ByteSIM’s plans that carry “Unlimited” in the name are not truly unlimited. Each of those plans provides only 1 GB of high‑speed data per day; once that limit is reached the speed is reduced to 10 240 kbps. After the initial 1 GB the plan remains usable, but the data is throttled rather than remaining at full speed.
If an unlimited data experience is desired, ByteSIM does not offer such a plan for Guernsey. Instead, the provider offers several fixed‑data options, such as 50 GB for 30 days, 20 GB for 30 days, 10 GB for 30 days, and 5 GB for 30 days, all with tethering allowed. For travelers who anticipate heavy data usage, a fixed plan can be a more cost‑effective choice than the capped “Unlimited” options.