Hello @Stefan94a,

That's a good question, and I will elaborate on this. There are a set of activation rules in place, and the first rule that sets the tone for the others to follow is that the validity of a subscription or license cannot exceed 5 years in total. This means that once you get to this threshold after entering multiple activation codes in Central, subsequent codes will no longer be accepted, at least until the validity starts to drop below the maximum limit.

As for the number of slots supported in Central, there isn't really a limit for them, and by this I mean that their number can be cumulated by activating multiple subscriptions, as the main purpose of multiple licenses in the same account is usually to be able to protect multiple devices, divided of course between subscriptions.

However, from the technical perspective, it is not recommended to have more than 50 devices across multiple home user subscriptions in Central, but not because more devices would not be protected, but because exceeding this number may cause display problems in Central, since the home user account was not actually designed to accommodate such a large number of devices, and a requirement that exceeds 50 devices falls more into the realm of business/enterprise products.

If you have multiple activation codes, I think one solution would be to redeem them in separate accounts, and then subsequently extend their validity by adding more codes, keeping in mind the total validity limit of 5 years.
Of course, the formula depends on how many mobile devices you wish to protect, and for how long. For example, you could have 10 Central accounts to protect 10 mobile devices, and then extend the validity for each one until all remaining activation codes are used. Or any other combination available, 31 devices protected for 1 year, 5 devices protected for multiple years, depending on how you choose to split them.
It's really up to you. 🙂

I hope the information is useful.

Regards,

Alex