iPhone 8 Plus - Screen Glitch Upon Powering on Device

Hey All,

I recently bought the new Sprint iPhone 8 Plus and noticed a glitch that flashes briefly during the initial start up screen (Black screen w/ white apple logo). The glitch is rectangular shaped and is about 1/8"- 1/4" in height and the width of the screen if held vertically. It's really faint but visible enough to grab my attention the first time I powered on the phone. I went ahead and returned that phone back to the Apple store as a defect and got a replacement. Brought the replacement back home only to find out that it has the same exact issue! Chatted with apple support and they informed me that they are not aware of this being a known issue. So do you guys think it's a legitimate issue, coincidence, or am I being too paranoid because I spent a boat load of money for the phone?

Bright side is that the issue doesn't appear to have any impact on the display when operating areas such as home screen, apps, camera, etc. I mean how often are you going to be manually turning off/on your phone anyways, right? But at the same time, hoping the glitch is not a precursor to display issues that may occur down the road.

Please let me know if you all are seeing the same issue, as I want to get some feedback before returning the phone back to store.

Details are as follows

Device: iPhone 8 Plus 64GB Space Gray

Condition: Brand New

Carrier: Sprint

iOS: 11.0.1

Store: Apple Store

Frequency: 90% 9/10 tries

Steps to reproduce:

1. Power off device and power back on while holding phone vertically

2. Observe start up screen (Black screen w/ white apple logo)

Result:

A faint glitch will flash on screen

Notes:

Tested on both stock and latest iOS firmware with the same results.