"There are changes on the way to the way Crown solicitors are structured and funded [that will mean a] reduction in funding to this office.
"We had to look at the model that we had and the number of senior people that could be maintained. We had to restructure.
"It's always been my plan to make a move anyway. [The changes] just brought that forward by no more than two years."
Mr Pilditch emphasised it was not a "sour grapes decision" to leave and he had enjoyed his time here.
"The changes in the system were a great time to reflect on where I was and my plans long term," he said.
He was looking forward to the challenge and flexibility of being an independent barrister where he expected to do a mix of criminal and regulatory work, prosecutions and white collar crime.
He will also remain on the Serious Fraud Office panel.
Mr Pilditch said he had given Crown Law months of notice to ensure a smooth transition for the incoming Crown Solicitor.
While he wouldn't comment on whether anyone within his firm had applied for the Crown Solicitor warrant, he said Gordon & Pilditch was "well placed to continue providing the service".
"The current intention of the firm is to continue to offer the service but that's up to the Government to decide," he said, adding he had no say on who his replacement would be.
Crown Prosecutor Amanda Gordon is the other partner of Gordon & Pilditch.
