Tretocephalus stay smaller and leaner. I suspect yours will fill out and look more like frontosa with time. It's possible to be fooled by some photos, but in person not really, not if you're familiar with them.
There are two, and only two, species of Cyphotilapia gibberosa and frontosa. Sp. North was suggested by some who were not biologists when they speculated that 6 and 7 barred frontosa would be split into two species, about the early to mid 2000s. This included a French cichlid writer who spent time diving the lake. It never happened. Scientists determined the difference in bars was superficial and that other characteristics confirm them as the same species. It escapes me at the moment the year this was done, 2007 maybe, but it was before 2010. For a while some held on to hope that they might yet be split, but it never happened. (meanwhile, Ad Konings never liked that they split giberrosa into a separate species)
For varying reasons, sp. North persists in the minds of some after all these years. You see it on some forums, even an occasional article, but it's essentially an outdated name that was never official in the first place. The correct name is still (Cyphotilapia) frontosa.
Pretty sure yours are frontosa, not giberrosa. The giberrosa "mask" can be ambiguous vs the frontosa eye bar when they're small, but even at smaller sizes giberrosa generally have more blue and a different look than yours. It's possible they haven't settled yet and some time and better photos would make a difference, but I think frontosa based on those photos.
With some exceptions, male frontosa humps, both 6 and 7 bar types, tend to be larger or more exaggerated than on gibberosa. And Tanzanian giberrosa tend to get larger humps more frequently than Congo coast giberrosa.