We don’t know what enhancements or problem fixes the new software provides because Apple doesn’t provide details on what’s contained in refreshed firmware upgrades for the AirPods.
Although there are no standard means to upgrade the software on the AirPods, firmware is typically installed over the air while the AirPods are attached to an iOS device. After a short length of time, putting the AirPods in the case, connecting the AirPods to a power source, and then pairing the AirPods with an iPhone or iPad should force the update.