It might be helpful if I added some context to my avoidance and advance payments outline.
According to the impact summary HMRC expect to issue payment notices to around 43,000 taxpayers. Over £5 billion of tax is anticipated to be paid.
It is then expected that a range of different legal challenges will arise, including judicial review, closure applications and disputed enforcement activity. There is a stated committment to providing additional resources to HMRC, including so-called “Flexible legal resource options”. Presumably code for outsourcing to third party providers; if so this would be a significant depature from working practices to date.