For one, defender Andrey Pedan, who scored a few goals for his team, was knocked out of the OHL playoffs tonight. If you read his twitter, it sounds like his bags are already packed. Pedan thanked "everybody for supporting [him] in Guelph," and "that [he] will be missing every one of you." He then proceeded to retweet a few dozen Islander fans, so yeah, I'd say he's headed eastward. Pedan doesn't yet have an ELC with the Isles.
Ryan Strome's IceDogs also lost tonight as did Scott Mayfield's Denver Pioneers. Strome has pretty clearly outgrown the OHL, scoring 34 goals and 94 points in 53 games. For Mayfield, he could still return to school as he is finishing up his sophomore year of college but all signs seem to point to him leaving early.
Pedan and Mayfield could join the Sound Tigers on ATOs, amateur tryout contracts, which would not apply towards the Isles 50-contract limit for this season (they're at 48 contracts right now). Those two could also sign ELCs, which act separately from ATOs, that kick in next season. Strome's ELC would slide another year as long as he doesn't play more than six NHL games; AHL games don't count towards the slide rule. Strome would also need an ATO to play for Bridgeport.