The Depository Trust & Clearing Corporation (DTCC) has pushed back the release of its blockchain-based post-trade system for derivatives by several months, in part because of complications created by Brexit.

The official line from the U.S. central securities depository (CSD) is that the delay, which has not been previously reported, is to allow for additional testing of the revamped trade information warehouse (TIW).

A spokesperson for the DTCC told CoinDesk:

“The project is progressing well. DLT and cloud development have been completed and we continue to conduct in-depth industry-wide testing with our clients, vendors and technology providers. However, to ensure that this technology is implemented in a measured, prudent and most secure manner, we have allocated additional months for testing, to ensure that firms are 100 percent ready.”

But a person familiar with the technology testing process said the upset about to be caused by the U.K.’s departure from the European Union was also a factor behind the postponement.

The previously scheduled release of the new TIW system coincided with the week of Brexit, which is slated for Oct. 31.

“When Brexit happens, everybody has to open up a whole set of new accounts outside of the U.K. They basically have to kind of split their records; there have to be their E.U. records and their U.K. records,” said the source.

Assuming Brexit does happen, the source added, firms have an additional set of operational work to do and DTCC wanted to separate that from going live with TIW.

There are also other timing issues to do with market implementation, including new regulations from the Commodity Futures Trading Commission (CFTC), the source said.

DTCC did not provide an exact date for the re-scheduled release.

The transformation of the TIW from mainframe to cloud, using a distributed ledger designed by technology provider Axoni, is uniquely challenging because when it’s turned on, the legacy system will be switched off.

The TIW handles settlement and processing of $11 trillion of credit derivatives worldwide, making the upgrade, announced in January 2017, one of the most significant enterprise blockchain projects.

Union Jack image via Shutterstock