BB-A-USDT is a USDT interest bearing token staked to Aave from Balancer Boosted Pool.
Boosted Pools bring the best of both worlds to Liquidity Providers and Swappers. Swappers get access to deep stablecoin liquidity with near-parity exchange rates while Liquidity Providers get their liquidity positions sent to external protocols, such as Aave.
These versions of Stable Pools don't directly hold the stablecoins themselves, but rather hold the pool tokens of nested Linear Pools, which, for the Aave example, maintain proper balances of TOKEN and aTOKEN.
