The two landlords hoping to secure a judicial review of the legislation restricting mortgage interest tax relief on buy to let investments have unveiled their legal team.
It was already known that Omnia Strategy LLP was the firm involved, with a team led by Cherie Blair CBE QC. It is now known she will be joined by Conor Quiqley QC, an expert in state aid law, and Sarah Hannett, a public law and human rights specialist.
The story so far is that landlords Steve Bolton and Chris Cooper are arguing for a review of section 24 of the Finance (No 2) Act 2015 - which includes the proposed restriction of mortgage interest tax relief at a basic rate, even for higher rate-paying landlords.
Osborne proposes that some individual buy to let landlords would not be able to deduct full mortgage interest costs from their rental income before calculating a taxable profit.
However, Omnia claims this discriminates against individual landlords by denying them the same rights as, for example, large scale corporate and institutional landlords which can "set their finance costs off against their income and be taxed only on their profit".
Bolton and Cooper says that if they get the go ahead for the review - it is believed there will be a decision soon by a judge, based on papers already submitted to the court or possibly following a short hearing - there will then be a full court hearing.
This could last between one and three days, and would probably be in the autumn.
The landlords have started a second round of crowdfunding to raise an additional £50,000 - and have hinted they may require up to £250,000.