Each version of this integration matches a specific build of Unreal Engine 4. Here is what has changed between the 2017.2.7.6667.1010 and the 2017.2.8.6698.1053 release of the integration (in addition to upgrading to the new Unreal build).

Unreal Engine 4.17/4.18/4.19/4.20 - Wwise 2017.2.8.6698.1053

• WG-36728 Added a Commandlet allowing to generate SoundBanks from the command line.
• WG-37990 Fixed: (Xbox One) Crash when loading large SoundBank in a packaged game not using PAK files.
• WG-38420 Fixed: Crash when Sequencer AkAudioEvent section is garbage collected while playing.
• WG-39091 Made RoomComponent and LateReverbComponent compatible with level streaming.
• WG-39097 Removed build warnings about missing samples folder.
• WG-39113 Fixed: (iOS, Linux, macOS) No audio for Shipping configuration.
• WG-39115 Fixed: Obstruction refresh issue on Portals.
• WG-39170 Fixed: Invalid argument passed to UnloadBank.
• WG-39301 Fixed: CancelEventCallbackCookie does not properly use user-supplied cookies to cancel.
• WG-39393 Fixed: (Switch) Invalid State Group ID.
• WG-39833 Fixed: Reduced the number of calls to SetAuxSends when unnecessary.