Riot Games have changed the substitution ruling, allowing 7-player rosters for the upcoming playoffs in the NA LCS. Previously, the 2018 NA LCS Rulebook stated that a 7th-player may only be used:

where (i) the team’s Starters are comprised of three Resident players and two non-Resident players; and (ii) the team’s Reserve is a non-Resident player. In this circumstance the team is required to maintain a Seventh Player that is a Resident player. This Seventh Player requirement is intended to protect against situations where a Resident player becomes unable to play during the LCS playoffs and the team would be unable to field a roster with its non-Resident substitute due to the prohibition of three non-Resident players as Starters. A Seventh Player cannot be utilized in a playoff game unless a Resident player becomes unable to play due to: (i) illness; (ii) incapacity; (iii) personal emergencies (as determined in the sole discretion of League officials)

When asked for a statement from commissioner of the NA LCS, Riot Grza, he commented, "we haven't updated the rulebook to reflect the change but we've informed all teams. We made it official last week but have been talking to teams about it for a few weeks". When asked if this would be implemented for the EU LCS as well, Riot Grza was unsure due to the leagues functioning independently. Follow the reporter on Twitter at @ggIzento for more League content.