Essentials:

Bamboo Blocker has no home server, so there is no server the app can send data too.
Bamboo Blocker doesn't embed any kind of analytic hooks in its code, so it is unknown for Bamboo Blocker what you do with the extension.

Filter updates:

The only time Bamboo Blocker connects to a remote server is to update the filter lists and other related assets. This ensures that the filters are updated for optimal ad blocking, if the filters are not updated to the latest standards the filters would get out-dated over time.

Data Storage:

All data that is you see with Bamboo Blocker, like number of elements blocked since install are locally stored on the own browser. Bamboo Blocker does not have any access to this information, so your usage data is completely private.

That is all.