That would be super easy with API ! I recommend to use the meraki.py library ( https://github.com/meraki/dashboard-api-python/ )
Python 3.6 -> pip install meraki
Then you could use something like that :
apikey = "your api key"
orgid = "your org id"
newaddr = " your new addr "
inventory = meraki.getorginventory(apikey,orgid) # Return your inventory
for mr in inventory:
if "MR" in mr['model']: # if the model contains MR ( AP ) could be MS , MX , MV
mrinfo = meraki.getdevicedetail(apikey,mr['networkId'],mr['serial']) # To get the device info that contains the adress
if "OldAdress" in mrinfo['address']: # To check if the device matches your old adress
postnewaddr = meraki.updatedevice(apikey,mr['networkId'],newaddr) #Push the new addr
This is mostly complete. I didnt run it , so double check it before doing so. And I'm not responsible if something bad happens. Always try your calls before running them in a production environnement.
Hope it helps !