The plans to trigger Article 50 at the beginning of 2017 could be derailed by various legal challenges. We've covered some of them before.
The most recent one is hoping to go before the High Court in mid-October saying that the Prime Minister must get Parliment to vote before she invokes Article 50. Specifically they can say that she can not use Royal Perogative to bypass the need for Paraliment to vote before Article 50 is invoked.
Currently the crowd funding pledges stand at £45,000 with 12 days to go with a target of £50,000. People's Challenge to the Government on Art. 50: A Parliamentary Prerogative. It seems likely that this will be funded.
This follows on from from and earlier story that came 10 days after Brexit where another firm of London lawyers Mishcon de Reya said they were looking to challenge Brexit on the same basis. Brexit Day 10: Top law firm to challenge Brexit decision.
This latest challenge is using the legal firm of Bindmans LLP.
Source: The Indepentent - Brexit legal challenge: High Court bid could derail Theresa May’s EU exit timetable