Where are the message sent to when ack deadline exceeds

Question

If multiple subscribers share the same pull subscription, when a message arrives at on subscriber, but it takes too long for the subscriber to ack the message, will the message be resent to the same subscriber or other subscribers? What if the subscriber dies before ack, which subscriber will the message be resent to?

Answer 1

Once a message that was delivered to a subscriber expires, it immediately becomes eligible for redelivery. Note that the message may or may not be delivered to the same subscriber binary; Cloud Pub/Sub gives no guarantees on “subscriber affinity/stickiness”.

In the same manner, if the subscriber binary dies before the ack can be sent, the message will be redelivered to another binary, after the ack expiration deadline.