TaiG, the jailbreaking team released version 2.1.0 and soon after that released 2.1.1 with a supposedly Substrate fix for Cydia. Well, it seems that TaiG has removed those versions without giving any major reasons but claiming that they might have had issues in them and were for internal use. Well check out the details regarding TaiG jailbreak for iOS 8.3.
The current version of TaiG and Cydia does not have a proper Substrate that can be used for jailbreak tweaks. For those of you who are not familiar with Cydia Substrate, it is basically a framework which jailbreak tweaks hook onto for proper working. A huge portion of tweaks on Cydia rely on the Substrate to work, therefore most of the tweaks you download now for iOS 8.3 are not compatible and will therefore not work.
TaiG and Saurik (Cydia founder) are currently working on fixing the Substrate for iOS 8.3 – which is extremely important for a proper working Cydia. Therefore when people saw that a new version of TaiG was available, many actually thought it was the one with the Substrate but it actually wasn’t.
From what TaiG mentioned, the new versions were for internal use only and therefore are not official. Even if you have the version 2.1 and above of TaiG, it is recommended that you do not use them until the new official versions come out.
Until then you will just have wait and use the tweaks that are compatible now.