I guess the next two weeks will tell us if the next main game will be released this year or not. GF has a very clear tradition of revealing or starting campaigns in May. There's still June but June has E3 and Pokemon was never revealed there but rather promoted. July is the movie month so nope, August is too late for this year to make a decent campaign

HGSS and ORAS were revealed in May, XY and SM started their campaigns for good in May

So whether we're getting Alola 2, Alola+Kanto, just Kanto reremakes, Sinnoh remakes, Kalos 2, Kalos+Alola we'll find out either very soon or next year