Embodiments described herein relate to methods and apparatus for determining which 5 of a plurality of subframes are repetition subframes, wherein repetition subframes are subframes scheduled for use by abase station to transmit a repetition of a system information block. A method comprises receiving a first mapping comprising information designating a subset of the plurality of subframes as invalid subframes; and determining, based on the first mapping and a second mapping, which of the 0 subframes designated as invalid subframes are repetition subframes, wherein the second mapping comprises information designating at least one of the subset of the plurality of subframes as a repetition subframe.