"It took one year before the take action level was reached, not that it is flying one year above the highest alert level. Anyone familiar with HUMS knows extremely minor damage can light off lower alerts that have no impact on safety and even the highest are set with significant margin".
I thought HUMS was a trend forecast, so if there is a trend that is monitored getting closer to failure mode over a relativity short period, perhaps ?.
I did not think it had been above safe level for a year if it had surely that would would be irresponsible at least
I do appreciate there has to be a level that is to low to warrant action but as the trend was progressing in hind sight a look may have been a good idea.