iTunes Connect上的某些屏幕截图未显示

I can successfully upload five iphone / ipod touch screenshots to itunes connect. I have always kept the screenshots the same resolution, whether five at all 320 by 480, or five at 640 by 960. I dont mix the resolutions. I have tried from different browsers, including chrome, firefox, and safari, and from different computers and internet connections. The same result happens. I see all five, and I can log off and log back in to iTunes connect ans still see all five. But after about 15-30 minutes, when I log back in I only see the first and last screenshot. So I see two screenshots instead of five. I have been working with contact us at itunes support but no resolution has happened yet. Has anyone else experienced this issue or found a fix?I can successfully upload five iphone / ipod to