In a prior study note, Kuo predicted that Apple would establish both a 31.6-inch display along with a 16-16.5″ MacBook Pro in 2019, so it is not completely clear if the 15-17″ MacBook identifies another laptop or if Kuo currently considers the 16-16.5″ MacBook Pro is coming a couple of years later than he originally anticipated.
An excerpt in Kuo’s research note, obtained by MacRumors:

We feel that miniature LED, compared to OLED, will be much more suitable solution to provide wide-color gamut (WCG)/high-contrast/high dynamic range (HDR)/local dimming features for its longer life and no burn-in issues for Apple’s moderate – and large-size products targeting at productivity rankings.
Apple plans to establish a trio of new products with Mini-LED backlights over the subsequent two years, including a 31.6″ screen in the second or third quarter of 2019, a 10-12″ iPad in late 2020 or early 2021, and a 15-17″ MacBook in the first half of 2021, based on renowned analyst Ming-Chi Kuo.
We predict that Apple will launch an all-new layout 31.6-inch screen, a 10–12 inch iPad and a 15–17 inch MacBook outfitted with a mini LED backlight unit (BLU) in two –3Q19, 4Q20–1Q21 and 1–2Q21.

Kuo thinks that the 31.6-inch screen”will aim a very high-end position” and attribute an”all-new design.”

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