I'm a front end guy, and I've been hiring a back end developer overseas to develop my API for me.
We've been testing and developing at AWS on their EC2 on a t2.micro instance. My backend guy has quoted me an absolute fortune to upgrade to a t2.medium plan (around 15 hours), but far less (1 hour) to upgrade to a t2.large plan.
Why is upgrading to a medium instance far easier than upgrading to a large instance?
EDIT: Developer has now changed his mind and is stating that all the T2 instance types cannot be upgraded to without a full reinstall. Apparently we can upgrade to m3.large, but no T2 instances. Note the picture below: