JSFiddle - React, Tailwind, and code Playground

HTML

<img src="http://dummyimage.com/150x100/f00/000">

CSS

img {
    position: absolute;
    left:130px; 
    top:150px;       
}

.rot {
    -webkit-transform:rotate(90deg);
}

JavaScript

// Needed to read the "real" position
$.fn.adjustedPosition = function() {
    var p = $(this).position();
    return {
        left: p.left - this.data('dx'),
        top: p.top - this.data('dy')
    }
};

$(function() {

    var img = $('img'),
        pos;
    
    // Calculate the delta
    img.each(function() {
        var po = $(this).position(), // original position
            pr = $(this).addClass('rot').position(); // rotated position
        
        $(this).data({
            dx: pr.left - po.left, // delta X
            dy: pr.top - po.top // delta Y
        });
    });
    
    // Read the position
    pos = img.adjustedPosition();    
    alert(pos.left + '/' + pos.top);     
    
    // Write the position
    img.css(pos);
    
    // Read the position again
    pos = img.adjustedPosition();    
    alert(pos.left + '/' + pos.top);
    
});