What are Milestones in FronTiers? Are these included in the Tiers?

What are FronTiers Milestones?

Milestones are unlocked as a FronTier reaches certain thresholds of the total funding. If your Tier level includes Milestones (more information can be found on the individual FronTier's About section), you will receive all the unlocked rewards once the FronTier ends. Milestones are available to view on the “About FronTier” tab.