There is a lot of discussion earlier in the help text about when to use --overwrite:
If branches have diverged, you can use 'bzr push --overwrite' to replace
the other branch completely, discarding its unmerged changes.
If you want to ensure you have the different changes in the other branch,
do a merge (see bzr help merge) from the other branch, and commit that.
After that you will be able to do a push without '--overwrite'.
It is possible that the help text could be cleaned up a little bit more.
There is a lot of discussion earlier in the help text about when to use --overwrite:
If branches have diverged, you can use 'bzr push --overwrite' to replace
the other branch completely, discarding its unmerged changes.
If you want to ensure you have the different changes in the other branch,
do a merge (see bzr help merge) from the other branch, and commit that.
After that you will be able to do a push without '--overwrite'.
It is possible that the help text could be cleaned up a little bit more.