If one of you withdraws consent
This is the structural weakness of a mutual consent divorce, and it is better understood before you file than discovered at the second motion.
Consent has to exist at both motions. Not only when the petition is filed — at the moment the court passes the decree. Either of you may withdraw it up to that point.
What the courts have held
In Hitesh Bhatnagar v. Deepa Bhatnagar (2011) the Supreme Court confirmed that a party may withdraw consent, and that where consent does not subsist, a family court cannot pass a decree under section 13B. The court's satisfaction at the second motion is satisfaction that both parties still want this, and it is not a formality it can dispense with.
So a petition that has cleared the first motion is not a decree in waiting. It is an agreement that both of you are still free to leave.
What actually happens
The petition fails as a 13B petition. The court cannot grant mutual consent divorce without consent. The matter is dismissed or the petition is treated as withdrawn.
The marriage continues. Nothing about the first motion dissolved it.
The settlement does not automatically bind you. A settlement filed in support of a petition that fails is in an awkward position. Whether any part of it can be enforced — and a payment already made, or a property already transferred, is a different question from a promise not yet performed — depends on what the document says, what was actually done under it, and the view the court takes. It is litigated, which tells you it is not obvious.
The other party's options change. They are back to a contested petition under section 13 on a statutory ground, with everything that follows: evidence, cross examination, years rather than months.
The eighteen-month limit does the same thing quietly
Section 13B(2) requires the second motion not before six months and not after eighteen, counted from the presentation of the petition. Miss the outer limit and the petition lapses whether or not anyone changed their mind.
In practice this is a more common failure than a deliberate withdrawal. Two people who separated amicably stop paying attention, nobody diarises the date, and the file dies of neglect. Put the second motion window in a calendar the day the first motion is recorded.
One party simply not turning up at the second motion has the same effect as withdrawal, because the court cannot record the statement it needs.
What reduces the risk
Finish the settlement before filing. Most withdrawals are not a change of heart about the marriage. They are a change of heart about a term that was left vague, and the person who feels short-changed uses the only leverage they have.
Perform what you can before the second motion. An obligation already discharged cannot be reopened as easily as a promise. Where a one-time payment is agreed, when it is paid matters.
Keep the gap short. Apply to waive the six months where the facts support it. The longer the window, the more time there is for circumstances to change. See the cooling-off period.
Stay in contact. Not as sentiment — as risk management. A silent counterparty is how an eighteen-month limit is missed.
What a court cannot do
A family court cannot dissolve a marriage on the ground of irretrievable breakdown, because that is not a ground listed in the Hindu Marriage Act. In Shilpa Sailesh v. Varun Sreenivasan (2023) the Supreme Court confirmed it can do so under Article 142 of the Constitution, including where one party does not consent.
That power belongs to the Supreme Court alone. People read about those judgments and arrive expecting their own family court to apply them. It cannot.
What to do next
If consent has already been withdrawn, the question is no longer about section 13B, and the next decision — whether to restore the settlement or to file contested — is the one worth taking advice on quickly.
If you are still at the drafting stage, this page is the argument for finishing the settlement properly. A guided session is where that gets done.