1. A method of handling recordings in an implantable device, the method comprising: (a) prioritizing data using a priority index, the priority index based on a severity level function, the data stored in data blocks of a fixed buffer; (b) initiating a first recording in an active buffer, the first recording storing pre-event data associated from a signal set; (c) detecting a first event and a type of the first event; (d) determining a sensing configuration based on the type of the first event, the configuration specifying a time duration having a pre-event time and a post-event time that indicates a total amount of time to record data of the first event; (e) copying the pre-event data associated with the first event beginning at the pre-event time into a data block of the fixed buffer having lowest priority data as determined in (a); (f) saving post-event data associated with the first event until the post-event time in the data block of the fixed buffer including the pre-event data; and (g) re-prioritizing data using the priority index, the data stored in data blocks of the fixed buffer.