Trying to ‘select’ a date for co-termination in the co-termination licensing model is almost (if not actually) impossible. You can’t just add one year licenses as you’ll actually increase your device count, not just extend/reduce the existing licenses. And when you do a renewal you renew all devices at once for a given period, normally a multiple of whole years.
The only way you may be able to do it is if you have a very nice Meraki AM when you do your renewal. Even then if you do get the co-term date you want, the minute you add another device to the organisation it will change again.
If your customer really wants a known renewal date then they need to move to the ‘per device licensing model’. In that model each license is assigned to a specific device, and you can purchase 1-day licenses to shift the renewal date for that device. That way you can purchase the exact number of days to get the renewal date you want.
See her for more information, https://documentation.meraki.com/General_Administration/Licensing/Meraki_Per-Device_Licensing_Overvi...
