Method in a user equipment (120), a user equipment (120), a method in a base station (110) and a base station (110) for setting values of system parameters used within a wireless communication system (100). A first set of parameter values and an associated first tag is sent from the base station (110) to be received and stored by the user equipment (120). Further, a second set of parameter values and an associated second tag is sent from the base station (110) to be received and stored by the user equipment (120). When the base station (110) determine to change system information parameters, a command tag is sent, to be received by the user equipment (120), which apply the set of parameter values associated with the tag corresponding to the received command tag.