SpaceX is set to launch its Falcon 9 v1.1 rocket on Sunday — the first launch of the rocket since its attempt at a launch on June 28, failing to arrive at the International Space Station.

The blastoff will mark the first use of the upgraded Falcon 9 rocket, which will lift 11 ORBCOMM communications satellites from Cape Canaveral to space.

The spacecraft is now featuring Merlin 1D engines for payload fairing and lengthened fuel tanks. The increase in fuel tank size will essentially provide enough fuel for the rocket when it'll give a shot for a recovery landing.

The launch was supposed to go ahead on Saturday, Dec. 19. However, the company was held back by a problem when testing the engine for static fire, a usual practice that essentially involves having the rockets restrained and exhaust dissipated in the atmosphere.

Perhaps more interesting than the fact that the Hawthorne-based aerospace manufacturer plans on launching the upgraded Falcon 9 rocket is the company's plans on trying to land the rocket on solid ground for the first time. Previously, the company has tried to land the rocket on a floating barge.

While the company hasn't officially confirmed that a landing will take place, on a message board it was reported that an email had been sent to workers at the Kennedy Space Center on Friday, Dec. 18, detailing access exclusions for an hour after the launch.

"Following the launch, SpaceX may attempt a landing of the Falcon 9 rockets first stage at Space Launch Complex 13 on CCAFS. Should there be an anomaly, personnel are to shelter in place and avoid being next to glass windows and doors," the email reportedly said.

SpaceX is in a pretty high-stakes position. The company is competing with Boeing to win launch contracts with NASA, and while the American space agency has ordered contracts from both SpaceX and Boeing, it has ordered two from Boeing and only one from SpaceX.

The first launch of the Falcon 9 v1.1 spacecraft will be on Sunday, Dec. 20 at 8:29 p.m. EST. View the live video coverage of the countdown, launch, and landing on Spaceflight Now.