State lawmakers last month approved a $2.4 billion funding package to build the full rail line to Ala Moana Center. Last week the project’s federal partners said they never determined whether a scaled-back, less costly alternative to Aloha Tower would have worked instead.

That so-called “Plan B,” which would have deferred seven rail stations in town and a key transit hub at Pearl Highlands, was proposed halfheartedly by rail officials in October 2016 as a way to potentially finish the over-budget transit project on the $6.8 billion it had available.

Even as they floated the idea, Honolulu Authority for Rapid Transportation officials made clear in their reports that they believed stopping the line at Aloha Tower was a dubious and deeply flawed plan. The move might lead to more construction delays, cut ridership in half and leave the state’s largest-ever public works project with virtually no contingency cash in case of problems, they said.

In an email last week, the Federal Transit Administration said it “did not make a determination about a Plan B” because the city clearly preferred building to Ala Moana.

The federal agency, which is providing $1.55 billion to the project, already told the city it would not accept stopping about 5 miles short at Middle Street. But with the project in official recovery mode since last year, it’s been willing to consider other alternatives such as Plan B.

“The FTA has said, ‘Think outside the box and we’ll talk,’” former city Department of Transportation Services Director and HART board member Mike Formby said in May 2016.

HART spokesman Bill Brennan confirmed that the local rail agency did not get any word from the FTA “regarding feasibility or acceptability” of Plan B.

That has Honolulu Mayor Kirk Caldwell facing renewed scrutiny from some rail critics over testimony he gave Aug. 14 to a panel of mostly skeptical legislators, ahead of their special session to fully fund the project.

“Funding must be adequate to fully fund the project all the way to Ala Moana Center,” Caldwell told those lawmakers in his opening remarks. “The FTA will allow nothing less.”

Keli‘i Akina, president and CEO of the Honolulu-based conservative think tank Grassroot Institute of Hawaii, characterized Caldwell’s statement as misleading.

“After this revelation (by the FTA), it would be shocking if policymakers ignored a blatant attempt to manipulate the Legislature and conceal what was really going on behind the scenes,” Akina said in an email.

According to Caldwell spokesman Jesse Broder Van Dyke, the mayor was referring to the terms of rail’s 2012 full-funding grant agreement with the FTA, which requires the city to build a 20-mile, 21-station system to Ala Moana.

About an hour later into his Aug. 14 testimony, Caldwell told state Sen. Gil Riviere (D, Heeia-Laie-Waialua) that “I don’t think the FTA has weighed in at all at what will be acceptable to them” regarding rail’s ultimate size and scope.

Local leaders have paid attention in recent years to what, if any, changes to rail the FTA would accept. The agency could pull some or all of rail’s $1.55 billion in federal funding if it declares the city in breach of contract.

Last fall, as state lawmakers prepared to discuss another rail bailout package, some of them hoped to bring FTA representatives to Hawaii so they could clarify their position on the transit project. That briefing never took place, however.

House Speaker Scott Saiki (D, Downtown-Kakaako-McCully) said he and his colleagues never received confirmation of whether rail’s Plan B would have been feasible. During the Legislature’s special session, the only direct contact the lawmakers had with the FTA occurred during a conference call in U.S. Rep. Colleen Hanabusa’s downtown Honolulu office on the proposed funding deal — and whether the federal agency was likely to accept it, Saiki said.

Nonetheless, Saiki said, most state lawmakers deemed it necessary to build the entire project to Ala Moana Center — not stop the line at Aloha Tower.

HART submitted its final version of rail’s recovery plan — complete with financing to build all 20 miles and 21 stations — on Sept. 15. The Honolulu City Council approved the plan earlier this month, and the FTA is still reviewing it.