Render help

[The Provident Poet]

Do presets change the export?

Ok, I have a H.265 file I want to export at 4096x1716 pixels. I usually select the 4k UHD preset from the drop down which is 3840x2160. Then I just change the pixel ratio to 4096x1716. But does this mean the file is just a 3840x2160 file upscaled or is it actually true 4096x1716. Because if I try to select a smaller size such as 480 sd or 1080p it will not let me upsize the ratio to 4096x1716. Of course there is no preset for 4096x1716, but im wondering if selecting the preset then changing it affects my end file in any way. Would it look better to just set it to a custom file at 4096x1716?