The mix-up surrounding when most swaps would need to be cleared arose after the CFTC established two separate deadlines: one setting an effective date in which the clearing mandate begins and another by which market participants must be in compliance.

via Swaps Rule Sends Wall Street Into Clearing Limbo: Credit Markets – Businessweek.

If anyone has more info on the underlying issue, send it over. The story as written needs careful reading.

Useful chart here: http://deltastrategygroup.com/wp-content/uploads/2012/10/Delta-Strategy-Implementation-Timeline-10022012.pdf or download direct from here