A squid invasion lands in late May, while late June is surprisingly woolly.
If a (now removed) release list on Nintendo of Europe’s website is correct, then Splatoon is coming to Europe on May 29 and Yoshi’s Woolly World is launching on June 26.
Splatoon was previously confirmed to launch in May. The May 29 date is almost the exact same day as when Mario Kart 8 launched last year. Yoshi’s Woolly World was most recently set for release in the first half of 2015. If Woolly World launched on June 26, then it would just sneak into the first half of 2015.
Additionally, the listing mentioned that Kirby and the Rainbow Paintbrush and the Puzzle and Dragons Dual Pack are coming on May 8, and Code Name: S.T.E.A.M is set for release on May 15.