It has been confirmed we will NOT get any Minecraft Bedrock 1.17 caves & cliffs features this week in beta, we do have only a handful of fixes which are listed below.

PLEASE READ before participating in the Minecraft Beta:
- Joining the beta will replace your game with a work in progress version of Minecraft
- You will not have access to Realms and will not be able to join non-beta players while you’re previewing the beta
- Any worlds played while in the beta cannot be opened in previous versions of the game so please make copies of worlds to prevent losing them
- Beta builds can be unstable and are not representative of final version quality
- The beta is available only on Xbox One, Windows 10, and Android (Google Play). To join or leave the beta, see ms/JoinMCBeta for detailed instructions
Bug Fixes
General
- Fixed a bug that caused mobs such as Pillagers to hide away from sunlight
- Fixed an issue where some mobile devices would lose audio after suspend and resume (MCPE-101027)
- Fixed a bug that caused Vertical Knockback to be too weak
- Fixed an issue in RTX when flying around would stutter and have poor frame rate (MCPE-103532)
- Added UI start up screen to inform players if they are on outdated graphics drivers
Technical Changes
- Fix so that old command versions use the previous position instead of current one
- Fixed issue where ‘query.cardinal_block_face_placed_on’ no longer worked with ‘on_player_placing’
- Changed texture atlas padding size from 0 to 1 when disabling mipmap
- Fixed issue of blocks listed in the “minecraft:block_placer” component wouldn’t work correctly
MoLang
- Geometry, Material, and Texture variable names can once again contain dots
source: https://feedback.minecraft.net/hc/en-us/articles/360051928792