Former national security adviser Michael Flynn filed court papers on Tuesday to withdraw his guilty plea related to allegedly lying to the FBI about his contacts with Russia’s ambassador to the U.S.Why now: The move comes only one week after the Justice Department shifted its position on his punishment, recommending he serve up to six months in prison, and comes days before his Jan. 28 sentencing.Why it matters: Flynn was the first Trump associate to face charges in the Mueller investigation, pleading guilty to the FBI in Dec. 2017.He now says he deserved to withdraw his plea because of the government's "bad faith, vindictiveness, and breach of the plea agreement."Read Flynn's appeal here: Go deeper: Prosecutors recommend Michael Flynn serve up to 6 months in prison