Abstract: Isochronous ultra-wideband (UWB) audio transport must deliver a complete service data unit (SDU) before its presentation deadline; fragment reception rate and aggregate throughput do not directly characterize this objective. We formulate admission and online service over a periodic calendar of finite exchange opportunities, explicitly accounting for fragmented SDUs, bounded attempts, calendar alignment, and timing uncertainty. For equal-duration, freely assignable opportunities, an interval-demand condition characterizes finite-job reservation feasibility, and an earliest-deadline-first construction realizes a feasible reservation. A separate necessary capacity bound identifies loads that cannot sustain complete-SDU delivery even with no transmission errors. For online overload control, we study a deadline-aware policy that discards an SDU when its outstanding fragments exceed the remaining eligible opportunities. Across 3,456 replicated scheduling runs and 432 supplemental sensitivity runs, pruning raises eight-stream burst-loss timely completion from 45.441\% to 59.399\%, a paired difference of $13.958\pm2.080$ percentage points (pointwise 95\% interval). At four streams, round robin instead attains slightly higher completion, while heavy overload causes pronounced per-stream imbalance. A finite design enumeration and an evaluated multi-stream fragmentation envelope quantify the interaction among scheduling, payload overhead, and capacity. These findings distinguish provable admission conditions from online deadline salvage and expose the aggregate-throughput versus per-stream-service tradeoff in UWB audio scheduling.