You probably should ask 48 support but I suspect that there are still no plans to introduce it otherwise they would have sung it from the rooftops...
http://www.48months.ie/help#ask-a-48-agent
Am about to get a 4G phone myself so would also love to see this made available.
Do they at least offersomething better than 3G?
Yes. H and H+, although I'm not sure which specific release versions of H+ they support.
https://telecomtalk.info/difference-between-g-e-3g-h-4g-symbols-we-find-out/121666/
Hope this helps.
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