The removal of the lifetime allowance introduces 'more complexity' and advisers need to quickly work out how their clients are affected, according to guests on the FT Adviser podcast.
At the Autumn Statement the government confirmed that it would be scrapping the lifetime allowance from early April, ignoring pleas from the industry for more time to prepare.
Speaking on the podcast Jon Greer, head of retirement policy at Quilter, said the new regime "gives us a bit more complexity".
He said: "Broadly speaking you have to account for any benefit crystallisation events, for want of a better word, that have occurred historically and bring them forward so they use up your new lump sum allowances.
"So broadly speaking if you do what they call a standard transitional calculation if you have used up 50 per cent of your lifetime allowance it looks like you'll have used up 50 per cent of your lump sum allowance but [...] you have this alternative transitional calculation which is to account that historically people might not have taken tax free cash.
"So it really requires advisers to have pretty good records because the onus is almost now on proving you didn't take tax free cash, so your transitional calculation of how much you have used up of your lump sum allowances could be very different.
"Then it's that whole process of providing that evidence to a scheme administrator so they then know how much lump sum allowance is left.
"It is baking in what I would say is unnecessary complexity into this new system. My concern is that we are on a real tight timeframe and to input these new nuances is really unhelpful."
Andrew Tully, technical services director at Nucleus, agreed advisers would have to pay particular attention to clients who had already taken benefits and how those would be impacted by the new regime since there were "lots of nuances".
He said: "The chancellor stood up and abolished the lifetime allowance charge but all the checks against the lifetime allowance still apply.
"It feels like the Treasury want to get to that position going forward but have to abolish the lifetime allowance so we seem to have got into a convoluted situation where we would probably be better staying where we are.
"That would be the simplest thing because there would be no system changes involved, communication aspects would be much lower. We're getting into the same position we're in today but we're going through a whole load of pain and difficulty to get there."
damian.fantato@ft.com