I'm absolutely not proposing anything of the sort, and I'm baffled that we continue to talk at cross purposes here.But the restock time can be different for different commodities and the game doesn't write that into the journal. So someone would need to manually find out how long that is and the trading clients neeed to be updated manualy.
I'm simply suggesting that the apps could grab the low-hanging fruit (in fact it's basically already on the ground ) represented by the journal MarketBuy entries which are almost (but not quite) as good as having a full market journal update on departure. (I accept that the fact that the apps don't do this is more likely to be for some good reason I'm not aware of than a failure to consider it.)
This would pretty much instantly make things massively better with low-traffic carriers in particular - where the stock levels of any given commodity are often less than will fit in a single ship, and where the market supply levels on EDDB/Inara are thus extremely untrustworthy as a rule.