Queries will be canceled if they are not completed within the time specified by the setting of "query.timeout" which is set to a default of 60 minutes.
Queries are queued in AtScale if the connection pool is saturated. The queue wait time is controlled by query.timeout, which defaults to 60m. That is the total queue timeout. So if a query sits on the queue for 35m, it will only have 25m to execute.