For any previous chart where you’ve marked a temperature shift, the app will automatically place your coverline. In your current chart, you can tap on your chart to place a coverline manually. If you’d like to edit the data for a particular day, you can now double tap on the day (instead of a long press) so not to interfere with coverline.
If you’d like to move the coverline, simply drag it up and down on your chart. Want to remove it? Drag it below your chart. Want to get it back to where the app placed it? Drag it above your chart to return to automatic placement.
For more information about what coverline is and why it is a helpful part of understanding your fertility check outthis Blog post.