Hodder has blamed the delay on problems with pouring the fairfaced concrete used in the design.
However, a project source said last year that delays were caused by difficulties in installing the centre's complex roof, which involved two or three costly redesigns while on site.
Costs on the project have escalated with the delays. A district auditor's report last year said project costs had risen from £15m to almost £25m.
A spokesperson for Hackney council was unable to give an opening time for the leisure centre as it was in the process of deciding whether to outsource its management.
It is also understood that main contractor Gleeson is likely to claim losses that it incurred as a result of the overrun.