Avalanche does not use the same pricing mechanism as Ethereum does. Ethereum uses its consistent block times along with the gas per block as the indicator to set the BaseFee.
In Avalanche, that idea doesn’t make sense. Avalanche allows asynchronous block issuance (there is not necessarily a consistent block time). It targets every 2 seconds but varies depending on if there are more transactions to put in a block.
Avalanche uses the amount of gas used over time to calculate the modifications to the BaseFee. If there are enough transactions that are willing to subsidize the cost of producing a block earlier, then it can generate another block.
Essentially, while there is still space in the blocks being issued, there is no space in the time window they were issued in.