Is there a rule or is it experience? Baking times

[Curfew]

If a recipe gives the baking time for a cake in a round tin, how much do you alter the baking time if you want to bake it in a loaf tin or in cup cakes? Do you need to change the temperature too?

A loaf tin will take longer as the cake is thicker so it takes longer for the heat to penetrate to the centre of the cake, and cupcakes will bake faster for the opposite reason.
i tend to do a loaf tin cake at a lower temperature for longer so the outside doesn’t overcook

An 3 egg 8” round sponge will take 23/30 min at 160°
The same mix will take about 40/45 mins in a loaf tin at 150°
As cupcakes probably about 15/18mins at 160°
(all fan oven, add 20° for non fan)