Does queue pushes with etaMillis hold subsequent normal pushes in Google App Engine?

[Gudrat Hasanli]

If I am pushing to the Google App Engine Task Queue like that...

Queue queue = QueueFactory.getDefaultQueue();
queue.add(TaskOptions.Builder.withUrl(“/url/path“).param(“number”, 10)).etaMillis(absoluteTime);

...will it then hold all the future normal pushes without etaMillis until the absoluteTime is reached?

If yes, what if I wanted first to push something to be executed in 20 minutes and then push something to be executed immediately? Given that we cannot create queues in queue.xml file programmatically, meaning that we cannot create parallel queues in runtime, does it mean that it's better to schedule tasks with cron rather than using etaMillis?

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