Banner image are last to load. why? above the fold is more important for speed

 Its a known thing that one of the key factor of website speed is showing above the fold content first.

But it seems that squarespace giving lower priority for banner images that supposed to load first (they loaded at the end or after few of the below the fold elements). on my home page its the latest element it load before favicon (after other images).

Because its such a simple tweak, i hope squarespace team will notice and fix it. As "first paint" is a top criteria now.