Redash not working after upgarade to v7 from v6

[2020-08-13 05:47:37,759][PID:124][ERROR][ForkPoolWorker-2] Task redash.tasks.refresh_queries[c9ca69d8-06a5-4b5d-a1ed-f94b1ceae3a2] raised unexpected: ValueError(“Attribute ‘schedule’ does not accept objects of type <type ‘int’>”,)

[2020-08-13 05:47:37,759][PID:124][ERROR][ForkPoolWorker-2] Task redash.tasks.refresh_queries[c9ca69d8-06a5-4b5d-a1ed-f94b1ceae3a2] raised unexpected: ValueError(“Attribute ‘schedule’ does not accept objects of type <type ‘int’>”,)

could see the above error in ECS worker logs and the console for redash fails with below.

Internal Server Error

The server encountered an internal error and was unable to complete your request. Either the server is overloaded or there is an error in the application.

Configuration:
RDS Postgres instance
docker container on local mac is created with v7.0.0.b18042 and then pushed as an ECR image to AWS account.

That image is used to launch redash as ECS in AWS with autoscaling.

Please let me know if there is any known issue similar to this or if i am missing something very basic ?

this issue is fixed

What do you mean with '“correct” REDASH_COOKIE_SECRET?