I was running the Service Plan for the Windows 10 enrollment within System Center Configuration Manager 1602 (Current Branch).
Unfortunately the option the use the same Software Update Group over and over again is missing:
The missing option is often used with the Automatic Deployment Rules (ADR), where you can configure to add the found updates to an existing Update Group:
But without the opportunity to “Add to an existing Software Update Group” you will end up with an update group and a deployment pointing to the collection every time the service plan was running. Please vote on uservoice to tell Microsoft they should add this option to the service plans aswell:
Always keep in mind to check uservoice if you see an improvement to ConfigMgr, maybe someone had already posted it, then you can only vote for it, have a look:
https://configurationmanager.uservoice.com/forums/300492-ideas