Cloud Spot Instance Idle Timeout and Minutes left in hour

Hello,

I'd like to be able to use the Idle timeout and Minutes left in hour together in a logical AND, but they currently appear to be working as a logical OR.

I only want my instances terminated after

- at least X minutes of Idle Time and there are Y minutes left in the hour and the instance is currently idle

The current behavior seems to be 

- X minutes of Idle Time or there are Y minutes left in the hour and the instance is currently idle

This currently has the odd behavior of shutting down all my instances at the same time, even if they were used within the Idle Time. The reason I want a "minimum idle time" is because Windows EC2 instances are very slow to boot, so it costs a good portion of the hour to terminate one and create a new one. 

The docs don't clear about how these two settings are supposed to work together. 

https://confluence.jetbrains.com/display/TCD10/Agent+Cloud+Profile

• Terminate instance idle time: Specify the period (in minutes) for TeamCity to wait before stopping an idle build agent. More than one build may run on the same virtual machine.

• When idle, specify how many minutes are left to the end of hour: Specify how many minutes before the full hour an idle instance should be stopped: this allows avoiding charges for partial hours if your virtual machines are billed in whole hours, e.g. Amazon EC2 instances (since TeamCity 2017.1).