Timeslot with text

Hello,
I don’t want users to see the start and end times inside the timeslot. I saw that I can remove the end time, but the start time remains, which could create confusion because I have different times for the same service (which unfortunately the plugin does not let me use because it provides only one duration per service). Using a code, is it possible to make a text appear in the timeslot instead of the time (for example the voice “appointment”)? I remember there was a code that allowed this, but I can no longer find it in the Plugin FAQ page.
Thank you