Hi,
Thank you very much for the details, it looks like a minor miscalculation from the body uncollapsed margin. I believe I already fix that calculation for the upcoming release, but it is not a simple fix, as some core files need to be edited for it.
As a temporary measure, please try this custom CSS:
.header-banner-display .asp_r {
margin-top: 50px !important;
}It should add the missing top margin when the header banner is enabled. You may remove this once the next update is released.