Does the express language of 21 U.S.C. § 851 requiring prior written notice of the particular conviction the government seeks to use to enhance a mandatory minimum sentence grant the government an implicit right to change the particular conviction post-plea and without the defendant's consent?

Is appellate review of the above question precluded by an appeal waiver which exclusively provides "the defendant retains the right to appeal a sentence imposed above the sentencing guideline range determined by the Court or above any mandatory minimum sentence deemed applicable by the Court, whichever is greater"?

Does the express language of 21 U.S.C. § 851 require prior written notice of the particular conviction the government seeks to use to enhance a mandatory minimum sentence