Hi, Daniel.
Thanks for your question. It’s been 58% for certain scenarios for a long time, like if there are 3 columns of information in the meta details area of an event, I think.
There were some recent CSS tweaks to make the map not look bad when there were not 3 columns of information, such as when there’s no Organizer at all for an event. (You can peruse the Release Notes if you wish.)
These modifications may have impacted your theming.
Please let me know if you need help with anything specific on your site–if yes, please share a link and describe the issue in detail, possibly sharing an annotated screenshot.