You already can apply for a special permit to operate a drive above 590Hz, through DHS or DOD, I can't remember which now. They will investigate you and your business and if it is for domestic use and you are not exporting anything, you can likely get a variance. This is not new, the requirement has been in place since January 15th. But if you were exporting and did not have a drive already limited to 590Hz, you had to get the permit to export. Now that the limit is in place in firmware, the only people required to get the variance are those not exporting and needing the higher frequency. That's far far fewer people.
This does not only apply to PowerFlex, ALL drives must comply and most other countries have complied already. The US was just the last country to enact this, and Rockwell is one of the few remaining US drive mfrs., so it appears to be something new to us.