Notwithstanding the obvious ethical goals, we all know that driving equality and diversity forward is imperative to brand protection, employee retention, recruitment and ultimately revenue generation. As an employer, there also are serious legal consequences in failing to keep up. The law says your training must be up-to-date and effective.
In a recent tribunal decision, Allay (UK) Ltd v Gehlen  UKEAT 0031_20_0402, a company was criticised for only providing training two years prior to an incident of racial discrimination. The fact that this training had faded from memory, as demonstrated by the incident in issue, meant that the company was unable to benefit from the relevant legal protections available.
Tailored refresher sessions should be provided regularly so that your employees are clear on how to identify and report harassment.