Hello @MarkG96159 ,
It appears this is an issue caused by the Gmail iPhone app's automated clipping - meaning there's some small portion of the imagery used in the email that being clipped ever-so-slightly, along with required footer and a small portion of email's unused inner background.
Our higher level technical team is going to investigate further, and will be following up with you via email within the next four business days. However it's entirely possible that it's an issue that will need to be fixed by the app's devs.