Two of New Jersey Gov. Chris Christie’s (R) top aides have now given sworn testimony with different answers to questions about an explosive claim connected to the George Washington Bridge lane closures.

At issue is when Christie spokesperson Michael Drewniak first told the governor about an allegation made by David Wildstein, who until December was an executive at the Port Authority of New York and New Jersey. No one is currently disputing that during the first week of December, Drewniak told Christie about Wildstein’s claim: that he had mentioned the lane closures to Christie in mid September. The lane closures caused days of traffic jams in the town of Fort Lee, N.J., and some have speculated the closures were ordered as political retribution against the town’s Democratic mayor. But Drewniak’s account of his conversation with Christie exists on a different timeline than that given by Christie chief of staff Kevin O’Dowd.

The discrepancy came up Monday during O’Dowd’s testimony in front of the state legislative committee investigating the scandal. The questions concern an early December conversation that took place between O’Dowd, Christie, and Drewniak.

O’Dowd told lawmakers on Monday that he believes the conversation took place on Dec. 2. That was the day Christie announced his intention to nominate O’Dowd to be the state’s next attorney general. It was also the day the governor first publicly addressed the bridge controversy, even joking at the press conference that he had “worked the cones” on the George Washington Bridge during the closures.

“If it was Dec. 2, there was — Mike Drewniak came to see me in my office. My recollection is that he came to see me to congratulate me about a press conference that had occurred earlier that day, where the governor announced his intention to nominate me to be attorney general,” O’Dowd told lawmakers Monday, in response to questions from Assemblyman John Wisniewski (D), one of the committee’s co-chairs.

“At some point, the governor enters the room, my office,” he continued. “And Mike Drewniak then addresses the governor. And I believe that the nexus, the reason he raised the issue was, ‘You know, I know what you said at the press conference about the lane closures, something about the cones. You need to know that Wildstein is saying that, or Wildstein has told me that, he spoke with you, he mentioned to you, something about the lane closures at the 9/11 memorial service in lower Manhattan earlier this year.”

On Monday, O’Dowd left some room for error in his account by saying he was not “certain” whether the conversation took place Dec. 2 or some other “point that week.” But if his version of events is right, it raises a number of questions about Drewniak’s testimony recently in front of the same investigative committee.

Last month, Drewniak told lawmakers about a dinner he shared with David Wildstein on Dec. 4. Previously released documents have shown Wildstein and Drewniak exchanged emails mentioning the Dec. 4 dinner both before and after it took place. At that dinner, Drewniak testified last month, Wildstein first told him that he had talked to Christie in September about the lane closures. Drewniak testified to feeling shocked at the allegation.

“David was concerned about his reputation,” Drewniak told the committee. “And then says to me that other people knew about this. He had previously mentioned [former Christie campaign manager] Bill Stepien and [former Christie deputy chief of staff] Bridget Kelly. Now, he throws in ‘and I told the governor about this.’ And I was surprised.”

If O’Dowd’s version of events is right — if Drewniak told Christie about Wildstein’s allegation on Dec. 2 — it raises questions about when and how Drewniak first learned about Wildstein’s claim. In Drewniak’s version of events, he didn’t tell Christie about Wildstein’s claim until Dec. 5, during a conversation in O’Dowd’s office.

“The governor walked in,” Drewniak said. “I told him what [Wildstein] had said, and then I said, basically, ‘You’re not going to believe this, he’s now thrown you in, too.'”

Wildstein announced his resignation from the Port Authority on Dec. 6. Earlier this year, lawyers representing the governor’s office issued a report clearing Christie in the scandal, and pinning the blame for the September lane closures on Wildstein and former Christie deputy chief of staff Bridget Kelly.

Christie himself also appears to have addressed the conversation with O’Dowd and Drewniak during his interview with the legal team that put together his office’s internal report on the lane closings. In an “interview memorandum” summarizing Christie’s interviews with lawyers, the legal team wrote that regarding “any conversations with O’Dowd or Drewniak about the lane realignment, the Governor recalled that at some point in December, the Governor walked into O’Dowd’s office while Drewniak was there speaking with O’Dowd.” The report did not specify the date that the conversation took place, but Christie’s account seems to align more closely with Drewniak’s than O’Dowd’s version of events — although the issue of Drewniak communicating Wildstein’s claim is absent from the summary.

“The Governor recalled that Drewniak was talking about having dinner with Wildstein, which the Governor found surprising because he did not think that Drewniak and Wildstein were such good friends that they would have dinner together,” the document stated.

The governor’s office did not immediately return a request for comment on Monday.