Upgrading ec2 from t2.micro to t2.medium or t2.large

Question

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:

Answer 1

If you look at this page

http://www.ec2instances.info/?selected=t2.small,t2.medium,t2.large

The cost per hour is more for a small, medium and large

On our systems we routinely shut them down and restart them on a different instance type. This typically takes a few minutes and no software changes. Altering the application memory use might be required I suppose but this is a trivial change

If the extra charges include the hosting for days/months then the difference in pricing makes sense

Using "on demand" pricing for the US-East zone there is a $62 difference in price between a t2.small and a t2.large per month

Answer 2

As a daily user of AWS, I can say that the only operations when upgrading within the same generation of instances (here t2) is to resize the VM memory and threading configuration.

1 hour is reasonable as your backend developer should update its deployment script and redeploy the infrastructure, but 15 hours sounds like a typo to me.