However, the Lang Cat said this disruption had not affected new sales growth, with record gross inflows of £20.3bn recorded across the sector during the last quarter of 2017.
This is compared to £18.6bn in the third quarter and £17.7bn in the second.
Taking a holistic view of 2017, the Lang Cat said it was a “landmark year for platforms”, with gross inflows totalling £75bn and net flows at a “healthy” £42bn.
The net inflow winners were the combined Standard Life and Elevate business, which totalled approximately £7bn, while Aviva’s platform inflows were £5.8bn.
The firm said AJ Bell, Old Mutual Wealth (OMW) and Transact had also seen strong flows.
Mark Polson, principal at the Lang Cat, said: “As we’ve seen time and again, switching technology is brutally difficult even when it goes well – and it rarely goes well.”
He said he expects to see “some very interesting developments” in 2018 as OMW’s programme continues, and as Aegon starts to move retail advised assets from Cofunds onto its upgraded ARC platform.
“These exercises are a chance for the sector to show it’s learned from the issues of the past,” he added. “Outside of replatforming, we’ve just experienced our first platform IPO from Transact which seems to have gone smoothly, but there is always the danger that corporate activity distracts management from day-to-day operations.
“For advisers, this means continued uncertainty and, with more corporate transactions likely over the next 18 months and some replatforming exercises dragging on, it doesn’t look like it will end soon.
“We’re often asked how advisers should respond: we hate to be boring but for the most part, they should sit tight and wait to see how things pan out.”
Fundscape’s chief executive officer Bella Caridade-Ferrira told Portfolio Adviser earlier this week that while listings come with risks, it also means the business is held to higher standards of accountability and transparency.