The level of payment restructuring still needed to make providers RDR-ready could set back implementation beyond 2012, according to Lighthouse Group executive chairman David Hickey.
Between advisers and customers, remuneration changes are on course to be in place by 1 Jan 2013, says Hickey.
But the extensive adjustments providers still need to make to absorb the new adviser charging model could end up delaying the whole RDR implementation, he warns.
"Providers and life companies are saying it is going to be really tough to make the changes. If the providers cannot be ready by 2012 it will slow the whole RDR process," Hickey says.
Some companies admit they still have extensive work to do in order to meet the deadline, but they are hampered as further details are still needed from the FSA.
Steve Folkard, head of AXA's RDR execution programme, says: "If implementation from 2012 is possible, and we think it is, we need the details on RDR from the FSA in Q1. If we get this the 2012 target is realistic. If not, then it isn't."
Folkard believes the time frame need for most providers to transition to adviser charging is around 18 months, but AXA will not begin analysing how to carry out this process until they are sure of the details.
Providers are not compelled by the RDR to support adviser charging, though it is likely they will in order to remain competitive.
Danny Wynn, RDR and commercial director at Legal & General, says while the insurer can start to put products on the drawing board, uncertainty over disclosure requirements is a cause for concern.
"We need to know the disclosure required for different products in order to produce the personal illustrations for each product, especially regarding reductions in levies. The FSA has given us no hint so far. All quote systems and disclosures are a bit hamstrung without those details."
Standard Life says it is still "assessing the likely impact" of the proposed changes.
Stephen Ingledew, distribution strategy director at Standard Life, says: "The retail market is undergoing substantial change with the RDR proposals being just one factor for consideration.
"We have been reviewing our strategy and plans incorporating our views on the RDR and assessing the likely impact for our business and the industry as a whole."
The next RDR paper from the FSA is due out in March.
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