simply consider that Ms has a couple of teams working on "anything". It is quite natural that teams work on future projects at a time when even the current problem is not solved. A relative of mine works at Mercedes/Untertürkheim in the design area and he often tells me that they ship latest stuff and engineering is on over-next project ... just normal, same with MS ... These different build sections within MS represent all the same pattern and you cannot be sure that any build they show to you will be the one you'll finally see
Quick update: Few weeks ago (07/07/2015 to be exact) build number of builds compiled in th2 build lab jumped from 10165 to 10500. All evidence suggest that this jump occurred to make some space for RTMing Windows 10 as build number of RTM must follow some strict rules. The newest build in th2 build lab currently is build 10505. Talking about release date of Redstone, rumors suggest it's targeted for next Fall.
Why so MS can come up with food names for their OS's? nahhh MS has the wrist band i don't think they want to get fat. LOL! Imagine Windows 11 codename: Beef Wellington! (inside joke) i know there is no windows 11 coming ever. haha aLso its branch "RS1 branches are alive - rs1_onecore_mqbase1 has been detected!"