Update Data Team planning processes to use iterations instead of milestones

Why is this change being made?

Within the data team, our previous milestone cadences included 6 milestones per quarter. All milestones in the quarter were 2 weeks long, with the exception of 1 milestone which would be 3 weeks long (since each quarter has an uneven number of weeks). This quarter, we said we would trial having a 1-week milestone at the end of the quarter for planning purposes.

Suggestion going forward (starting on Wednesday Nov 8):

• Rather than having an odd 1-week or 3-week milestone each quarter, I'd like to propose that milestones are consistently 2 weeks long and that we switch from using Milestones to Iterations
• Reasons for sticking to a 2-week cadence
  • Since some planning meetings are scheduled on a biweekly cadence, it helps us to have the milestones/iterations run on a 2-week cadence as well
• Reasons for using Iterations
  • Iterations can be created automatically at 2 week intervals (i.e. we don't need someone to manually create milestones each quarter)
  • Iterations support automatically rolling over incomplete issues into the next iteration
  • This also mirrors how the product is intended to be used per our customer-facing (docs)
  • This frees up the Milestone field to be used for other purposes in the future (either as a tag for Quarter values, i.e. FY24-Q4 so that we can build reports and boards based on Quarterly OKRs, or possibly as a project milestone i.e. Customer 360 v1 - we don't have to decide how to use it now, but freeing up the Milestone field gives us options)
  • The functionality should mostly be the same, the main difference I see is that the Iterations are always named by date (i.e. we won't be able to name Iteration 1, Iteration 2, etc.) but it looks like that is planned work. It's currently tagged for the next release (16.6), although it may slide out.

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