An apparatus (10) comprising: at least one processor (12); and at least one memory (13) including computer program instructions (14); the at least one memory (13) and the computer program instructions (14) configured to, with the at least one processor (12), cause the apparatus (10) at least to perform: receiving (201) configuration information for enabling the apparatus (10) to measure a first set of Downlink (DL) Reference Signals (RSs) (302) and/or a second set of DLRSs (304), wherein DLRSs (302 #0 – 302 #4) of the first set of DLRSs (302) are respectively associated with a first set of DL beams (303), wherein one or more DLRSs (302 #1 – 302 #3) of the first set of DLRSs (302) are configured to be Quasi-Co-Located (QCLed) with at least one DLRS (304 #m) of the second set of DLRSs (304), and wherein DLRSs (304 #a – 304 #z) of the second set of DLRSs (304) are respectively associated with a second set of DL beams (305); receiving (202) information for enabling the apparatus (10) to determine a Quasi-Co-Location (QCL) assumption for a Channel Occupancy Time (COT), wherein the QCL assumption for the COT is indicative of the availability, for use for transmissions within the COT, of: at least one DL beam (305 #m) associated with the at least one DLRS (304 #m) of the second set of DLRSs (304), and one or more DL beams (303 #1 – 303 #3) associated with the one or more DLRSs (302 #1 – 302 #3) of the first set of DLRSs (302) and QCLed with the at least one DLRS (304 #m) of the second set of DLRS (304); and determining (203), based at least in part on the received information and configuration information, the QCL assumption for the COT.