Will unity auto change texture (skybox) resolution based on screen resolution ?

I am using high res skyboxes , I have dropped the Max size of the skyboxes to 1024.

what i'm wondering is if I need to set them to 4096 just in case unity automatically reduces and increases the texture resolution based on the screen resolution.

if I leave the Max resolution to 1024 , does that mean that unity will not be able to increase its resolution to 4096 ?(if unity actually auto change texture resolution) .