A single-stock was included in this inter-benchmark: North Sea Autumn Spawning (NSAS) herring (her.27.3a47d). This inter-benchmark process was put forward because of: 1) newly available natural mortality values and 2) a discrepancy in the handling of natural mortality (M). For the NSAS assessment, natural mortality is provided every 3–4 years by WGSAM. This is often associated with a rescaling of the assessment. At WKPELA 2018, a profiling method was developed to handle the introduction of new natural mortalities and in turn, alleviate the potential rescaling of the assessment. The method consists of the testing of the fit of the assessment model for a range of additive rescaling (fixed across years and ages) for M. The optimal fit of the assessment model is then taken as the additive level of rescaling to be applied to M. However, for the profiling performed during WKPELA 2018, a benchmark interim model specification was used. In practice, the assessment profiling should have been performed using the WKPELA 2018 final model configuration to ensure consistency in the derivation of additive rescaling. This discrepancy was only discovered at HAWG 2021 and has a consequence in the scaling of the assessment. In that context, this inter-benchmark process had the objectives of 1) updating the natural mortality for the NSAS assessment and 2) evaluate the methodology for handling newly introduced natural mortality vectors. These tasks subsequently led to the update of the assessment model and associated reference points. First, the newly available natural mortality values from WGSAM were found to be similar to the previous run and did not affect the assessment significantly. Second, the investigation of the profiling method showed that it brought consistency in the introduction of different natural mortality vectors. Its use was maintained with the intent to run such an assessment profiling at subsequent benchmarks. However, the method was also found to be sensitive to the introduction of new data points and model specification, particularly the introduction of a correlation structure in fishing mortality. This aspect together with better model diagnostics warranted the introduction of such a correlation structure. The new model yields a smaller SSB and higher fishing pressure. With this change in model configuration, new reference points were derived with an updated approach compared to WKPELA 2018. Blim and FMSY have been revised upward whilst MSY Btrigger is now smaller. With these reference points, fishing opportunities are overall increased.