At that rate, the final payment will be made in the last quarter of 2013.
BP played up its initial contribution, saying the company is making it ahead of schedule:
BP announced at the time that the first deposit of $3 billion to the account would occur by the end of the third quarter. BP has decided to make this deposit early to demonstrate its commitment to meet its pledge to restore both the livelihoods of those affected by the oil spill and the environment.
The DOJ is also "pleased":
We are pleased that BP made an initial contribution and has taken an important step toward honoring its commitment to the President and the residents and business owners in the Gulf region. We have made clear that the company still needs to ensure that the necessary funds will be available if something happens to the subsidiary that established the trust and we look forward to completion of an appropriate security arrangement in the near future.