How often does the BeforeBulkIndex event get fired in a user's lifecycle? Is it only once? My custom sort field can change quite often, and it might not have a value before the event gets fired. Will that be a problem?
That event gets fired before altered users get changed in the index, which varies by how often the job runs and how many changes need to be processed. You still will have to store this value somehow and read it when the event is fired
