The council's executive is due to choose between the two shortlisted consortia – Lend Lease and Key Property Investments – at its meeting on Tuesday 24 July.
The new schedule follows the last-minute cancellation of a special executive meeting at the end of February when the decision had been due to be made.
"We are on the eve of a very important and exciting decision, and both consortia are still firmly in the frame," explains Cllr Richard Thomas, executive member for regeneration.
"The selection of the preferred partner is a huge milestone for the regeneration project, and residents and businesses can be assured that the decision will lead the way to a fantastic future for Elephant and Castle."
Southwark Council is keen to stress that although it hasn't yet chosen its development partner progress has been made on the wider regeneration of Elephant and Castle, albeit by private developers such as Multiplex with their 43-storey Strata SE1 development on the Castle House site
450 households have already been rehoused from the Heygate Estate as preparations continue for its demolition. As long-term tenants move out the vacant flats are used for temporary accommodation.
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