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As part of the The Agile Coach - What is Scrum playlist, there is a video on Sprint Planning Basics.
The 3-step process used at Atlassian involves:
Does this resemble what your team does?
I'd score my team X X X right now for following this process. That just means like many of you our agile adoption process is iterative!
How does your team plan sprints?
Kudos. IMO it's not just legitimate, but often preferred way to organize the work.
I've used, and brought to others, "ScrumBan" since, well about 3 decades before it was popularized with a name. There are some reasons why it works, and circumstance when it's the far better choice. I haven't written that article, yet.<g>