To upgrade the old ones to have the new firmware & quality you’d need to change both speakers. While everything is more or less compatible, one old and one new ear speaker don’t work together:
Then you might have read it already, at some point in the production of the old version, the headband base was improved for stability, and I guess you can’t really know which version you’d buy with the old one.
Also note that the ANC did not get improved. So the wind issue will persist as with the old ones