I have no idea how this changed for me. One day I was doing it line by line like you, and the next time I had to update a search I had this other option to do it all at once! Whether this sticks around with the EBSCO interface updates or not, who knows! I'll enjoy it while I can :)

This probably doesn't help you now, but I've started saving my searches in an EBSCO personal folder, so when I need to rerun it I have the option to select all my search history lines and click "refresh search results" and it updates all the lines simultaneously. Unsure if this is a default setting

Can confirmed I got yelled at today, didn't eat in my office and felt better for it, damnit