Guaranteeing the duration of spot instances in GameLift FleetIQ.

Hi,

The GameLift FAQ answers your question in a negative manner (you cannot guarantee duration): https://aws.amazon.com/gamelift/faq/#Amazon_GameLift_Spot_and_FleetIQ

Question #1:

Amazon GameLift Spot instances offer access to spare AWS computing capacity 
at savings of up to 70% compared to On-Demand prices. However, Spot instances 
can be interrupted by AWS with two minutes of notification when AWS needs the 
capacity back. You can use this notification period to migrate or shut down games 
running on those instances. You can achieve cost savings while maintaining high 
game server availability with the use of FleetIQ, a new feature of Amazon GameLift 
that places new sessions on game servers based on player latencies, instance prices, 
and Spot interruption rates.

Subsequent FAQ in this section are worth reading as well

Best,

Didier