On Tuesday a majority of MPs backed an amendment - proposed by Sir Graham Brady and backed by the prime minister - calling for "alternative arrangements" to the Irish backstop, an insurance policy in the Brexit deal to avoid a hard border with Ireland.
The amendment calls for the backstop to be replaced with unspecified "alternative arrangements" to avoid the reintroduction of border checks in Ireland.
But if that proves impossible, Britain would remain aligned with the EU customs union after 2020, while Northern Ireland would further stay aligned to some single market rules, in order to keep the Irish border open.
The Brexit process has grown increasingly surreal since Parliament rejected Mrs May's divorce deal two weeks ago, leaving Britain lurching towards a cliff-edge "no-deal" departure from the bloc on March 29.
The chances of the Commons derailing her plans were also heightened when Labour confirmed it will back a cross-party amendment to push Brexit day back from March 29 to the end of this year and put Parliament in the driving seat on the way forward.
Since May's deal was rejected in the Commons on 15 January by 432 votes to 202, opposition and backbench MPs have been tabling amendments to the plans.
But May's official spokesman said she told her Cabinet that "in order to win the support of the House of Commons, legal changes to the controversial Irish backstop will be required".
May hopes that more MPs join them, under the joint pressures of time and of fear that their version of a ideal Brexit will be subverted by those who want no deal or no Brexit at all.
She said that she would seek "legally binding" agreements for any new deal but admitted negotiations would not be easy. May said if she has not struck a new Brexit deal by February 13, Parliament would get to vote, again, on what should happen next.
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FSIS is advising consumers to purge their freezers of the affected product as the contamination is considered a high health risk. Officials said consumers who have bought the products and frozen them should either return or throw them away.
The European Union has been adamant that there will be no renegotiation of the withdrawal agreement and that means no changes will be made to the backstop proposal; unless of course the United Kingdom shifts its red lines.
Pretty much two months to the day, and Yvette Cooper MP, a British Labour Party politician, has found her amendment shot down by 321 votes to 298 - a majority of 23.
A source in French President Emmanuel Macron's office said Tuesday: "The withdrawal agreement and the backstop are not renegotiable".
All Welsh Tory MPs voted against the no-deal Brexit motion except Guto Bebb, the pro-EU MP who represents Aberconwy.
And Ireland's European Affairs Minister, Helen McEntee, cautioned: "There can be no change to the backstop".
The dispute between Madrid and London has already threatened to derail the whole Brexit negotiation process, but a last-minute deal with Prime Minister Pedro Sanchez cleared the way in November for the 27 European Union states to approve the divorce package.
May, who will close Tuesday's debate, now hopes her Tory party will say clearly what it wants to change in the deal she's struck with the EU.
However, the amendment - originally proposed by Tory loyalist Sir Graham Brady (below) - was dismissed as "too vague" by Conservative MPs in the hardline Brexit European Research Group, which is chaired by Jacob Rees-Mogg. The plan aims to prevent the catastrophic scenario of crashing out of the bloc without a deal, but critics see as an attempt to thwart Brexit.
With more than a dozen amendments tabled, many by cross-party groupings of MPs, the outcome will depend on which ones are selected for voting by John Bercow.