After suffering a heart attack in October, United Continental Holdings Inc. CEO Oscar Munoz announced on Thursday, Nov. 5, that he will make his return to the company in the first quarter of 2016.

"I am on the road to recovery," Munoz wrote in a letter to employees.

"My time away will be a little longer than I would like, but based upon discussion with my doctors I will be back in the first quarter,"

The announcement serves to end the uncertainty regarding who will take the helm for United Airlines, which is considered to be the second-largest carrier in the United States based on capacity.

The airline company had previously named General Counsel Brett Hart to serve as acting chief executive. Members of the United's board had also been preparing for all possible outcomes that could result from Munoz's recent hospitalization.

Shares of the company remained the same in after-market trading following Munoz's announcement.

In September, Munoz took over as chief executive for United with the goal of improving company morale after suffering years of relations with labor members.

During his first month as CEO, Munoz traveled across the country to talk to travelers and employees about their opinions on how to improve the airline company.

Jeff Smisek, Munoz's predecessor, was forced to resign after the launch of probes that looked into the relationship between United and the Port Authority of New York and New Jersey.

The investigations centered on allegations that the airline added specific flights to Columbia, South Carolina in order to gain the favor of David Samson, the chairman of the port authority at the time, who reportedly owns a home there.

Acting CEO Hart said he will continue the agenda set by Munoz.

Financial services firm S&P Capital IQ, however, had lowered its rating on United's stocks from "Strong Buy" to "Buy" because of Hart's limited experience in the field of operations, customer service or finance.

A tentative deal between United and its maintenance employees has been put forward under Hart's leadership, which could lead to the first contract to cover both Continental and United technicians since the two companies merged back in 2010.

Photo: Roderick Eime | Flickr