MADISON, Wis. -- The chairman of the Public Safety Communications Oversight Board that manages policy and budget matters for the Dane County 911 Center said he first heard about the Zimmermann call April 3, the day after the University of Wisconsin-Madison student was killed.

Ron Boylan, also a Dane County Sheriff's Department chief deputy, said he was told by 911 Operations Manager Rich McVicar that there "may have been a call received from the 500 block of Doty Street regarding the Zimmermann homicide."

Boylan said that's according to his notes from the day. He also said he was told that as far as 911 officials knew, there was no problem with how the call was received or handled by the 911 center.

Boylan said that discussion sparked questions about how certain cell phone calls were pinpointed and dispatched, regarding the Dane County Sheriff's Department.

On April 14, Boylan said he had a follow up meeting about how 911 and his department respond to cell phone emergency calls. He said at that meeting there was no talk of any specifics about the Zimmermann call, but simply about "best practices" when it comes to locating different kinds of cell phone calls and how crews are dispatched.

He also said he and McVicar canceled the oversight board's regular monthly meeting on April 16 after they both concluded there wasn't anything to talk about.

The next PSC oversight board meeting is set for May. At that meeting, Boylan said he wants to know if any changes are coming about from the mishandled 911 call, how the center handles such calls in general and what the county's internal investigation found.

That internal investigation into the mishandled 911 call is expected to be released soon, perhaps later this week.

On Monday, Dane County Board of Supervisors Chairman Scott McDonell said he believes a mistake was made at the 911 Center and apologized. Dane County Executive Kathleen Falk has also drafted some letters of apology to Brittany Zimmermann's family and fiancé, according to a spokesman.

The apologies follow last week's news that the Dane County 911 Center received a call from 21-year-old Zimmermann's cell phone on the day she was killed in early April. However, a 911 dispatcher hung up on the call after apparently hearing nothing and then failed to call back, which violates 911 protocols. Police officers were never sent to investigate.