yeah, I found out roughly as much. I should say that I also noticed that the current version of libbitcoin doesn't have the same issue as bitprim. What happens in bitprim is they store all addresses from a block in a database somewhere and they have a cache for those addresses. However, the database doesn't know about testnet/regtest so it uses the default of mainnet. Not sure if a similar issue in libbitcoin might exist, the codebases have diverged a bit too much to say