On Thursday, the Associated Press acknowledged this apparent discrepancy when it quoted Maryland Senator Ben Cardin, the ranking Democrat on the Senate Foreign Relations Committee, as asking State Department officials, “Why did we misjudge so badly the date that is likely for [Iran’s] compliance?”

The remarks came in the midst of the committee’s hearing on the nuclear deal, sanctions relief, and Iran’s October ballistic missile test that was recently confirmed to be a violation of UN Security Council Resolution 1929 banning Iran from further development of missiles capable of carrying a nuclear warhead.

The response to Cardin’s question came from Stephen Mull, who is the State Department’s lead coordinator for nuclear implementation. It acknowledged that some projections were inaccurate, but suggested that this was simply because Iran had proven to be quicker than anticipated about its own implementation measures.

However, some of these measures reportedly did not even begin until this week, when the UN member states governing the International Atomic Energy Agency voted to close the file on the past military dimensions of the Iranian nuclear program. Other measures were slowed or halted mid-stream by Iranian Supreme Leader Ali Khamenei, who declared that implementation should not proceed until the PMD issue had been put to rest.

As of the Senate hearing, Iran apparently still had 8,000 nuclear enrichment centrifuges that needed to be disassembled and placed in storage. The Islamic Republic also must deactivate the core of the Arak heavy water plant so that it cannot produce significant quantities of plutonium, which constitutes an alternative to the uranium pathway to a nuclear weapon.

Projections of a January deadline for sanctions relief appear to have come almost entirely from the office of Iranian President Hassan Rouhani, and to have simply been accepted by Western policymakers and media. IAEA Director General Yukiya Amano declared on Thursday that Rouhani’s timetable was “not impossible.” But Amano acknowledged that this assessment depends upon simply taking for granted Tehran’s seriousness about clearing its obligations within the next two or three weeks.

Now the Christian Science Monitor has joined in reporting that implementation and sanctions relief are likely to come very early in 2016, as evidenced by the optimistic assessments of White House officials regarding Iran’s compliance and the “verifiable” nature of newfound restrictions on its nuclear program. But the Monitor also notes that there is still a great deal of wrangling about this within Western policy circles, with many members of the US Congress expressing a great deal more skepticism about Iran’s trustworthiness.

In some cases, those lower officials are simply advocating for a change in tack by the Obama administration and its allies. For instance, 21 members of the president’s political party wrote a letter on Thursday calling for a strong response to the two Iranian ballistic missile tests that have taken place since the conclusion of nuclear negotiations. Republicans and some Democrats have strongly criticized the Obama administration for effectively ignoring these activities and giving tacit approval to future misbehavior by Tehran.

In other instances of opposition to Obama’s policies, Congressmen are taking measures on their own in an attempt to weaken or undermine the nuclear deal before sanctions relief comes into effect. The Monitor reports, for instance, that an initiative is under way to prevent the White House from granting visa waivers to individuals coming from Iran.

While Congress does not have the power to follow through on this initiative explicitly for the sake of undermining the deal, the visa issue does provide lawmakers with an opportunity to emphasize Tehran’s general anti-Western sentiment and the ways in which too much openness between the two countries could be a threat to national security.

This argument is certain to receive considerable pushback from Obama and his allies, who generally embraced the Rouhani presidency as a victory for moderation in Iran more than two years ago. This sentiment has given European countries license to reach out for expanded trade relations with Iran, arguably showing even more eagerness for rapprochement than the Obama administration.

The Europeans have sent numerous trade delegations to Iran and have even invited Iranian officials to visit the West. A visit to France by President Rouhani was scheduled for November but was cancelled as a result of the terrorist attacks in Paris, in which ISIL militants killed 130 people. But now a new trip has been arranged for January, according to Reuters. It is thus possible that French President Francois Hollande will be hosting his Iranian counterpart soon after the suspension of economic sanctions.

Such incidents point to the international support that the Obama administration enjoys in maintaining its narrative about Rouhani as a source of moderation. But those Congressmen who dispute this narrative also enjoy international support, much of it from Iranians and Iranian exiles who see Rouhani as an entrenched regime insider who has broken all of his pro-reform campaign promises that were unrelated to negotiations with the West.

The disagreement over the Rouhani administration’s true character will certainly come to a fore over the next two months, as Iran prepares for elections to the Assembly of Experts, which is tasked with selecting a new supreme leader in the event of the sitting cleric’s death or removal.

The international media are largely characterizing this as a battle between hardliners and Rouhani’s allies, with the outcome potentially setting the stage for large-scale change after the 76 year-old Khamenei’s death. This description has been supported by bold comments from former Iranian President Hashemi Rafsanjani, who is regarded as a reformist by some and has suggested that the new Assembly of Experts could replace the concept of a single supreme leader with a council of leaders.

But the viability of this proposal is subject to serious doubts and on Friday Hassan Firouzabadi, the chief of staff of the Iranian armed forces, dismissed the idea as a “new trick” by Iran’s enemies to undermine the country’s “strong unity against America, Zionists and imperial enemies.”

There is no clear indication that any prospective candidates for the Assembly of Experts would support such a change, much less that they would be capable of winning their seats. Iran’s Guardian Council, which is directly appointed by the supreme leader, vets all candidates to major political positions in order to prevent the election of individuals who deviate too far from the clerical regime’s official positions.

The preliminary list of candidates certainly does include allies of the supposedly moderate Rouhani. But as Reuters notes, one of the most prominent of these is Hassan Khomeini, a grandson of the founder of the Islamic Republic. The presence of such a figure among the moderate wing of the field of candidates can easily be exploited by the US Congress and the Iranian resistance to highlight the notion that change cannot be expected to come exclusively from regime insiders.