You can repack BZP2 to BOZ using bzip2 program should you wish it. However, some BOZ files are just simply renamed BZP2 filles, so no conversion is needed.
Convert BZIP2 archive file to BZIP compressed archive file.
We have found one software suitable in our database for this conversion.
Linux/Unix software - convert bzp2 to boz on Linux
A free data compressor for Linux
Convert from bzp2 file format
The table with program actions contains information about what each program is capable of doing with their files. This may be a good pointer for further searches for certain file conversions and help you find the converter you are looking for if our search result is insufficient for you. However, it is far from perfect and may sometimes show results which are not really usable because of the nature of the software handles the files. So a conversion that appears as possible, just because of matched actions, may in fact not be possible.