Where the sentencing record is silent or unclear on which ACCA clause the court relied, do individuals asserting a Johnson claim bear the burden to prove the court relied solely on the residual clause?

QUESTION PRESENTED The question presented in this case is as follows: Where (1) the sentencing record is silent or does not clearly establish if the district court relied on the Armed Career Criminal Act’s residual clause, which the Supreme Court in Johnson v. United States, 135 S. Ct. 2551 (2015), found to be constitutionally infirm on vagueness grounds, (2) the Supreme Court in Welch v. United States, 136 S. Ct. 1257 (2016), determined to make Johnson retroactive to cases on collateral review, and (3) prior to Johnson district courts imposing sentences routinely did not specify on which clause or clauses of the Armed Career Criminal Act (ACCA) they relied because they were not legally required to do so, do individuals asserting a claim under Johnson in either an initial or successive motion to vacate sentence under 28 U.S.C. § 2255 bear the burden to prove as a matter of historical fact that it is more probable than not that the sentencing court relied solely on the residual clause, or are the procedural and substantive requirements for review and relief met under 28 U.S.C. § 2255(a), 28 U.S.C. § 2255(h)(2), and 28 U.S.C. § 2244(b)(2)(A), if the ACCA enhancement may have been predicated on the ACCA’s constitutionally infirm residual clause?