We have JIRA SW Standard annual subscription.
As per https://www.atlassian.com/software/jira/pricing its cost is $7750 for 100 users.
Premium for 1 year costs $15250.
In case I decide to move from Standard to Premium 6 months after the start of Standard subscription then:
1. Will I be charged only for Premium-Standard difference for the remaining period:
($15250 - $7750) / 2 = $3750
(and the license expiration remains 6 months from now)
2. OR my Standard subscription will be lost and I will be just charged for 1 year of Premium, i.e. $15250.
If possible, please give me a reference for your answer. But I will be glad for not referenced answers as well.