That's not entirely true, this isn't the full post. Juniors and Seniors will be combined into one division and will be the same as masters points/travel wise as far as i am aware. I wouldn't worry too much, im sure pokemon has a plan. They are a big business and can work things out along the way.
I just looked at the entire post on Pokémon.com and there was nothing about Juniors and Seniors. Not sure where you are getting your information.
Only Masters Division players who have opted in to participating in all available Play! Pokémon programs are eligible to participate in the Play! Pokémon Players Cup Online Tournament.
Yeh so anyone can make a new account and say they are a certain age and then enter. With no way to check the age of the person behind the computer it will be unfair because you could have a 35 year old with critical thinking skills masquerading as a JR. then they could end up playing a 10 year old with little critical thinking skills and minor experience. It's just easier to make it masters exclusive because then they can ensure that no cheating for age at least can be done(take this with a grain of salt because no one really knows why TPCI choose to make this move).
I get that part, although I think that is unlikely. My post was more on the cheating side than on the age, although I do think they have neglected the younger players for sure. I understand there are complications with the age for sure (being that they are all minors), but let's not forget that there are a number of Masters that are minors as it begins at 15 and up. I don't see how the issue for age is any different.
Where I was expressing concern was on the enormous amount of ways that players could cheat. I would imagine it is fully possible to have a number of players around 1 screen helping 1 player win against another by providing advice. This is just one of the ways I could see this happening. Furthermore, what happens when there are technical difficulties like an internet outage? They can't exactly reset the game and replay it. To me this just seems like a bad idea altogether. Points shouldn't be available in this kind of format. Watch during the event and after to see the forums light up with posts about cheating.