Relative URL to Events in Menu

I am currently setting up and testing The Events Calendar before moving it to our live site, so I want to set everything up with relative URLs that will work in both the test and live sites.
I have the Events slug set to ‘events’, so I can set normal links in WordPress to ‘events/’ and the URL is handled correctly, but I am having a difficulty setting up a menu to Events.
By default the Custom Link URL is an absolute URL – for my test site, this is “http://localhost:8888/Nancy/events/” – which won’t work when transferred to the live site.
If I delete the WordPress URL (“http://localhost:8888/Nancy”) the menu URL becomes “/events/” that attempts to link to “http://localhost:8888/events/” from the generated page – clearly not wanted.
If I change the menu URL to “events/” (or “events”), as I do elsewhere, that becomes “http://events/” (or “http://events”) in the HTML on the generated page – which is even worse. (It is actually changed to this in the Save Menu action of the Menus setup.)

Does anyone know of a way to get a relative address set for Events in a Menu?
Many thanks.