What has happened to 'add stop' in Maps app in macOS 15.4.1?

What has happened to the Maps app in macOS 15.4.1? The 'add stop' functionality has changed and additional addresses now need to be entered manually, instead of the user being able to add them from calendar entries.

Previously, I could click on an address in a calendar entry to calculate my route to that address, then click on another calendar entry to open that address in Maps and click 'add stop', and so on, to plan my day from there. Now, clicking on an address lets me route to it, but clicking on another address just wipes out the route and attempts to start from scratch. If I want to add another stop, I am forced to click 'add stop' and search for the next address manually - which is both time consuming and error-prone.

[Edited by Moderator]