Unless Robbie Amell is returng the The CW DC-verse in flashback, Ronnie Raymond will make his triumphant return on The Flash (or possibly Legends of Tomorrow). Will he get wind of Caitlyn Snow's (Danielle Panabaker) budding relationship with Jay Garrick (Teddy Sears)? Also, Franz Drame is confirmed as a series regular on LoT, so it would appear from a production standpoint, that Amell's appearance might be for only an episode or two. That is, unless the Legends of Tomorrow and Flash showrunners are setting the stage for a new Firestorm pairing of Ronnie and Jax.
The Flash returns from midseason hiatus on January 19th. DC's Legends of Tomorrow premieres on January 21st.