The script allows to move branches to the $prefix/

move_git_branches.sh

#!/usr/bin/env bash
# put the list of branches here
branches=(
  branch1
  branch1
)

prefix=rkh
author=Ruslan

for branch in "${branches[@]}"; do 
  data=$(git --no-pager show  -s --pretty="%an %d" "${branch}")
  if [[ "$data" =~ .*$author* ]]; then
    git checkout $branch
    git checkout -b $prefix/$branch;
    git push --set-upstream origin $(git status | grep "On branch" | cut -c 11-)
    git branch -D $branch
    git push origin :${branch}
  fi
done