Changing Proportions

Great plugin! Is it possible to change the proportions of a crop? If for example, I have a thumbnail set in my functions.php as:

add_image_size( ‘default’, 250, 9999, true );

Then I don’t seem to be able to change orientation or reduce the height of the crop; get this long skinny crop.

https://ww.wp.xz.cn/plugins/manual-image-crop/