Below is a list of the tiers and their builds in the order in which you would get access to them:
'The Half Cab' tier
Gives you access to development and prototype builds which are not actual game builds in themselves. These are standalone builds which would contain features being developed or prototyped, enhancements to existing features, etc. An example would be a a build with a grey-boxed gym for testing out verts & transitions. The estimated delivery date to have access to these builds would start as of January 2018 and would continue through to final release, whenever a build is made available.
'The Early Grab' tier
Gives you access to the earliest 'game build' in the form of Steam Early Access or Xbox One Game Preview. The estimated delivery date for this is May 2018.
'The Tre Flip' tier
Gives you access to Alpha & Beta builds of the 'Final Game'. They come after the Early Access / XGP and just before the Final Game release. The estimated delivery date for these would start in January 2019 for the Alpha and later for the Beta.
'The Fastplant' tier
Gives you access to the Final Game build. This is the last build that you would be receiving as it would contain all the promised game features and what we consider our official Game release. It would no longer be in Early Access / XGP as of this point. The estimated delivery for this is July 2019.