Analysts are reading clues from Apple's supply line to forecast the future of the next generation iPhones. The latest prediction is that the model with a 6.1" LCD - the budget iPhone with an expected price of $700 - will arrive late to the party. This iPhone will have an iPhone X-like design, which complicated things. The issue is with the LCD itself (being made by LG) - persistent issues with bleeding from the LED backlight reportedly pushed mass production back by a month. That's still better than the 6-week delay that was expected initially, but either way the 6.1" iPhone will launch...
Source: https://www.gsmarena.com/iphone_with_61_lcd_screen_may_launch_a_month_after_oled_models_due_to_a_delay-news-32425.php