Hi, @Jonathan
Thank you for posting in Microsoft Q&A forum.
Gradually make this software available over this period of time (in days)
Configure this setting for the rollout in each phase to happen gradually. This behavior helps mitigate the risk of deployment issues, and decreases the load on the network that is caused by the distribution of content to clients. The site gradually makes the software available depending on the configuration for each phase. The default value of this setting is zero, so by default the deployment isn't throttled. Don't set the value higher than 30.
If you set the time to 7 days and deploy to 200 devices, 28 devices /day gets the deployment approximately, but it's not an absolute average, there will be some ups and downs.
And if we set "configure the deadline behavior relative to when the software is made available" to Installation is required as soon as possible, the devices will install ASAP when they get the deployment.
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