[DTV]

the provisional schedules could be wrong, but Asia-targetted programming used to shift and they discontinued that.

Shift relatively to the UKT or to non-changed clock?
I think they still shift (relatively to UKT) Asia Business Report - this winter its first edition is at 2230 UKT, the last being at 0230 UKT, but in summer (since next week) it is 2330 UKT and 0330 UKT, respectively. This is not the case with Newsday as it would crash with World News America in winter.

Most Asia-targetted programming used to stick to the same GMT times all year (so shifting on UKT) until 2016, but, you're right, Asia Business Report is the exception.

“While the UK does have a small, but sizeable minority of African descent, I'm not sure their communities are particularly calling out for an African news programme - and, even if they were, showing it in one of the channel's stronger performing slots wouldn't be particularly wise given the limited nature of the programme's UK audience”.

Wow! Just wow!

What? This is just the reality of how television scheduling works. Even if we assume that British Africans will watch a Focus on Africa simulcast at 5x the rate that all Brits currently watch the average News channel hour (which I'm not really sure is at all true), that's an audience of about 20,000 - about one-sixth to one-eighth of the audience the slot currently gets. Even assuming some residual interest in African affairs from a portion of the channel's other viewers, British Africans would have to want to watch the programme at an absurd rate just to breakeven in viewer terms.

I'm not at all opposed to programming that serves a minority or niche audience, that is, after all, one of the purposes of public service broadcasting, but there are multiple reasons that such programming doesn't get put into the strongest-performing slots on general audience channels. And that is assuming that there is even a reasonable demand for this kind of programming among minority audiences, which nobody has provided any evidence for.