According to filings to the Canadian Radio-television and Telecommunications Commission (CRTC) by Thunder Bay Electronics (owner of CBC's Thunder Bay affiliate CKPR-DT) and Bell Media (owner of CBC affiliates CFTK-TV in Terrace and CJDC-TV in Dawson Creek),[citation needed] the CBC informed them that it will not extend its association with any of its private affiliates beyond August 31, 2011. In March 2011, CBC and CKPR agreed to continue working together for how many additional years?