I'd like to share something about GPS selection from Shirota's book (sorry in advance if this is off topic, I'll delete it if it is not appropriate).
The skaters submit their preferred two competitions to their federation. And at ISU meeting, first of all, the top 6 finishers in WC take in order a desired slot at one competition, and they do the same in the second round. Then 12 slots are filled out of 72 and 60 slots are vacant, and the skaters finished below the 7th place finally start to pick. But from here, in addition to the skaters' wish, there are various things mixed in the meeting such as strategies and intentions of each federation. Mostly, they want to send their skaters to the competitions which have less rivals, and if they host a competition, they want to invite the skaters who have popularity. Shirota gave an example of the past selection of the Japanese ladies. In 2005, Suguri and Ando could take their slots they had wished because they did well in WC, and Mao was her first senior year but she was already popular so every country wanted to invite her. But Arakawa, Onda, Nakano's selections were difficult to adjust, Shizuka was hoping to be in SA and SC but decided to be in CoC and TEB where her rivals also participated.
It seems the announcement from ISU is published every year, so I don't know if this is how it works this year. But I personally think if Shoma wants to be in NHK (I doubt it though, he may prefer the competition in overseas), he would be selected. And then I'm not sure if Yuzuru will be in NHK with Shoma, and I'm totally fine if Yuzuru competes in other competition since perhaps every country wants him to come
But Yuzuru has to be fully healed first