To quote LEADCOUNSEL;
"I know nothing about the change details for the FBI, but I would be shocked if it didn't have to do with budgets and smaller agents (females, more feminine males, etc.). Let's not forget that FBI agents are typically accountants, linguists, etc. They aren't typically tactical Joes fresh out of 11B school... This probably has to do with budgets, maybe a sweet HUGE deal (billions of bullets) on 9x19 contract, with free guns, who knows..."
Well stated, I find this the most plausable reason if a change is being considered by the FBI.