Quilter has said it is "confident" its replatforming will go smoothly because it has learnt lessons from the technology problems faced by its rivals - but it warned of "bumps in the road".
Last month the company's new platform went live for 100 advice firms in the first phase of the migration.
When asked what the company had taken from this first phase, Jeremy Mugridge, Quilter's head of UK proposition marketing, said more had been learnt from the company's rivals - such as Aegon and Aviva.
He said: "Our biggest learnings came from looking at other companies that had gone through similar technology upgrades. I'd say we probably learnt three main lessons from those companies.
"One would be don't go too early. So don't go until you are ready and you are confident that you can do this safely.
"The second one would be to keep your communications open and honest before and after the migration, and the third would be 'be prepared for bumps in the road'."
"These are big, big undertakings. There is likely to be a snagging list as we go forward. Be prepared for that and that will stand you in good stead.
"The feedback from the advisers in the first migration has been that us heeding these lessons has made a real difference and over the coming weeks we will reflect on the first migration and incorporate our first lessons learnt to ensure the second wave of advisers and customers enjoy an equally successful migration."
When Quilter terminated its contract with tech provider IFDS and switched to FNZ in May 2017 it said it had spent more than £200m on the platform, and expected to spend about £160m more.
In its results earlier this week Quilter said the replatforming process was "within budget".