It seems to only be available on the IPhone 15 series and is only available to plans taken after a certain date with certain handsets.
“To get 5G Ultra, you'll need a 5G Ultra-enabled device, any Pay monthly plan bought from 24 February 2023 onwards, and to be in an area covered by our 5G Ultra network”
Vodafone don’t officially support iPhone so if you call up and ask for it to be enabled for an iPhone they’ll say no even if you took your plan after the correct date (if you can get through to someone who actually knows what SA is…)
Someone on another forum had the right handset and plan taken after the above date but because they don’t live in a SA area CS declined to enable it despite working in one.
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