Terry, kindly note that once Tablet/Phone, RC, Craft are all fired up, if your tablet/phone is connected to the web the DJI GO should warn you if some firmware needs to be updated, including batterie(s), each having it's own firmware. Beware might take some time for GO app to detect new firmware available and of course preferabily to be done at home without rushing.
But kudos for your interest on this and you might want also take time to focus on important settings such as RTH (Return To Home) altitude, To Home behavior and more.
This forum has lot of useful information you can find.
Note also both RC and craft have strong high frequency outputs and might reduce visibilty of your home wi-fi router with possible impact of firmware download causing to be slow or held; make sure your tablet/phone get strong wi-fi signal from your home router.
Also make sure to never interrupt any upgrading process to avoid corrupted devices.
Hope does help a little.
PS: this was in context of update with GO app. Update with DJI Assistant discussed above is fine - just make sure to follow the steps as shown in video etc.
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