A rotating cast of WGN substitutes will fill in for Mark Suppelsa this month, Time Out Chicago’s Robert Feder reports.

Suppelsa, who anchors the 5 and 9 p.m. weeekday newscasts on the Chicago CW-affiliate, announced on Friday that he would take a month away from the anchor desk to seek treatment for an alcohol addiction. He expects to be back in June.

Micah Materre and Lourdes Duarte are handling Suppela’s responsibilities this week and next. Tom Negovan and Dan Ponce will anchor through the end of May, WGN news director Greg Caputo told Feder.

Frank Holland, who has been a reporter and fill-in anchor at Detroit’s WDIV for the past two years, is joining Chicago’s WGN as the morning co-anchor.

Holland will anchor the CW affiliate’s 4 a.m. to 5:30 a.m. broadcasts alongside Erin McElroy beginning September 12. WGN — which launched the early-morning broadcast about a month ago — has had Tom Negovan in the anchor chair on an interim basis while the station searched for a permanent anchor. Erin McElroy (formerly known as Erin Mendez) was assigned the 4 a.m. broadcast in April.

“We look forward to adding Frank to our AM team of personalities and we know our viewers will appreciate Frank’s energy and passion for good story-telling,” WGN news director Greg Caputo said in a statement.

Prior to joining WDIV, Holland was a general assignment reporter at News 12 Westchester in New York and WMGM in Atlantic City. He started his career in Fairbanks, AK, working at KTVF and KUAC.