The Finzels Reach scheme opposite Castle Park was due to be completed by 2017, providing 400 homes with offices, restaurants and a £3.6m bridge to the park.
Now developer Cubex Land, backed by property investor Palmer Capital, has bought all the existing debt to take control of the waterside scheme.
It currently contains 115,000 sq ft offices at Bridgewater House, which is 30% let to BDO and Barclays, and 195 apartments in three buildings.
The initial focus is to market 73 built but unsold apartments and lease remaining available Grade A office space at Bridgewater House.
Then Cubex Land will start a phased delivery of the project with completion expected in mid-2016.
This will mean delivering the Finzels & Cask project at the site, which has consent for 32 prime waterside residential apartments offering views of the Floating Harbour.
Seven other plots on the 4.7-acre site will be developed with a mix of new build and restored period buildings.
Gavin Bridge, Director of Cubex Land, Bristol said: “This project will play a crucial part in enabling Bristol to meet the growing demand for residential and office accommodation in its city centre.
“Cubex Land welcomes the opportunity to reengage with the local community and help bring the regeneration of this strategic site forward.”