The Navy plan to have its carrier and amphibious groups on a new deployment plan by 2018, but that could be disrupted by any of the most likely scenarios confronting the service virtually any scenario likely to be faced by the fleet in the coming years, from continued budget arrears to tensions abroad, uncertainty to an overseas crisis, a top Navy planner cautionedtold lawmakers Thursday.

Rear Adm. Jeffrey Harley testified that, head of the Navy's operations, plans and strategy office,said looming budget cuts, unexpected maintenance issues — such as the extra year the those faced by the carrier Dwight D. Eisenhower spent in the in its yards period — and training backlogs would an overseas and even a backlog training and maintenance cycles that upset the existing fleet response plan all could dreaildisrupt derail implementation of the so-called Optimized Fleet Response Plan.

Still, getting the Navy on track with its deployments is the best bet to get predictability back for sailors and the shipyards. If the Navy can't implement OFRP, officials have warned, the force will suffer through the loss of good sailors, shortened ship lives due to lost maintenance, and the hampering of the fleet's ability to surge continued degradation of the Navy's ability to surge in a crisis, and will rob its ships of service life.

"Ultimately, this is a pay-me-now or pay-me-later discussion," said Harley, the deputy head of the Navy's operations, plans and strategy office. "If we are not given time to reset the force through OFRP, and are forced to source beyond sustainable levels, we will remain challenged in all of these areas."

The dire characterization of the challenges facing OFRP come as congress struggles to pass a fiscal 2016 budget, just weeks away from it startingthe new year. Sources told Defense News in August that lawmakers were mulling a year-long continuing resolution, a stop-gap measure that locks in spending levels at the previous year's levels.

The hearing before a House Armed Services subcommittee was held to update lawmakers on the new deployment scheme and how it will benefit the Navy.

Harley stressed that getting the Navy to a more predictable deployment cycle will would benefit the shipyards, which would be better able to plan their hiring and work, as well as sailors, who could look forward to more predictable schedules.

Part of that will be the drive to get sailors to seven-month deployments, he said.

"We don't want to make these deployments too long," he said. "There are physical things that go wrong with our ships at about the 8-month mark and we have seen, through rigorous analysis, that extended deployments have impact on retention."

However, Harley said, the 7-month target also builds in some wiggle room for the Navy to flex to eight months in case of an emergency. The OFRP developed by Fleet Forces Command calls for a 36-month deployment cycle, where all of a carrier strike group or amphibious ready group starts basic training together before an upcoming deployment; first anticipated to be 8-months-long when unveiled in 2014, the chief of naval operations has said he'd like deployments to be a 7-month standard, barring a crisis.

The OFRP blueprint also lays out a sustainment period, when the crew maintains a high state of readiness in case the ship is called to surge deploy. Afterward, the ship will re-enter the yards to be repaired and upgraded. to be surged forward. 

Carriers have spent the last few years routinely sailing on long or unpredictable deployments; the Theodore Roosevelt recently completed the seventh month of what could be a 910-month supercruise.

The Navy is ultimately driving towards the ability to have two carriers deployed, with three ready to surge on short notice, Harley said. But that surge capacity has been largely eaten up by relentless demand for Navy forces by the four-star combatant commanders who oversee global operations.

"Combatant commander requirements continue to grow, and although we have historically sourced to capacity, we are routinely asked to surge or extend forces," Harley said. "In these cases, we are not so much generating new readiness, as we are consuming future presence and surge capacity."