So the Switch is currently at 7,5 millions sold this year, and there is still 7 weeks before Pokémon/Smash/New Super Mario Bros U Deluxe, so we can predict it will be around 8,7/9 by the third week of november, and then, if it sells around 7/8 millions from Pokémon to new year, sales will be around 16-17 millions. And around 3 millions from January to March, which would make it around 20 millions. Minus the (I suppose) 2.5 millions sold from january to march 2018, sales would be around 18 millions, which fall short from the 20 millions Nintendo expects to sell.
But in any case, 30 millions LTD by the end of the year doesn't seem too unrealistic.







