add_filter( 'woo_discount_rules_price_strikeout_after_discount_price', 'woo_discount_rules_price_strikeout_after_discount_price_method', 10, 2 );

function woo_discount_rules_price_strikeout_after_discount_price_method($item_price, $product){
	if ( ! ( is_shop() || is_product_category() || is_product_tag() ) ) return $item_price;
	if($product->is_type(array('variable', 'subscription_variation', 'variable-subscription'))){
		// Searching for the default variation
		$default_attributes = $product->get_default_attributes();

		// Loop through available variations
		foreach($product->get_available_variations() as $variation){
			$found = true; // Initializing
			// Loop through variation attributes
			foreach( $variation['attributes'] as $key => $value ){
				$taxonomy = str_replace( 'attribute_', '', $key );
				// Searching for a matching variation as default
				if( isset($default_attributes[$taxonomy]) && $default_attributes[$taxonomy] != $value ){
					$found = false;
					break;
				}
			}

			// When it's found we set it and we stop the main loop
			if( $found ) {
				$default_variaton = $variation;
				break;
			} // If not we continue
			else {
				continue;
			}
		}

		if(isset($default_variaton)){
			if(isset($default_variaton['variation_id']) && !empty($default_variaton['variation_id'])){
				$product = wc_get_product($default_variaton['variation_id']);

				global $flycart_woo_discount_rules;
				if(!empty($flycart_woo_discount_rules)){
					$discounted_price = $flycart_woo_discount_rules->pricingRules->getDiscountPriceOfProduct($product);
					if($discounted_price != null && $discounted_price != ''){
						$item_price = preg_replace('/<\/del> <ins>.*<\/ins>/', '</del><ins>'.wc_price($discounted_price).$product->get_price_suffix($discounted_price).'</ins>', $item_price);
					}
				}

			}
		}
	}
	return $item_price;
}