Republic Airlines (YX, Indianapolis Int'l) plans to retire the E145 from operational service have been thrown in disarray after Delta Air Lines (DL, Atlanta Hartsfield Jackson) announced it would be extending Delta Connection contracts for as many as forty-one of the Embraer Regional Jets through to 2021.

Aviation Week reports the move came as a near surprise as Republic executives had not expected Delta to exercise their unilateral option to extend contracts for thirty-eight ERJ-145s for an extra five years.

In a bid to simplify and streamline its operating structure and fleet, Republic Holdings announced in July last year that it would retire the ERJ-145s, in service with Shuttle America (S5, Fort Wayne Int'l), along with its E140s, E190s, and Dash 8-400s leaving it with only E170s and E175s.

The ERJ-145 phase-out was to have begun in August and would have run through to May 2016.