All three MPs have said that many of the people affected are public sector workers rather than wealthy individuals.
But according to HMRC 97 per cent of the individuals impacted worked as IT or management consultants, with less than 3 per cent being teachers or medical professionals.
In this morning's update HMRC wrote: "HMRC understands that customers who face large tax bills, or checks into their tax affairs, may find this stressful to deal with and need extra support.
"HMRC will treat individual cases sympathetically and appropriately, and will not require people to sell their main home to pay their disguised remuneration tax bills.
"To support loan charge users, HMRC set up a dedicated helpline, complemented by a team to provide extra support to those identified as vulnerable. It has redeployed staff to support scheme users and announced simplified payment arrangements."