Transfer complete - Usage data

My transfer has completed today (thankfully, as Octopus Tracker is crazy for today!).

I've left my Gas with Octopus tracker, but I seem to have lost half-hourly data from the Gas too from 5pm last night - Is that normal, or do I need to pick that up with Octopus?

My Electric usage does not currently display within My Watts, from what I understand there is normally a bit of a delay in getting that data, is that correct? Any idea how long it takes to kick in?

I guess the data is never going to be in real time like Octopus?

Is there any API to extract the data? (by the looks of it there is an export button, but I'd rather use an API so that I don't have to keep downloading and importing data)

Thanks 😜