gpcp_after_update_pricing

gform.addAction( 'gpcp_after_update_pricing', function( triggerFieldId, GWConditionalPricing ) {
    // do something crazy!
} );

gform.addAction( 'gpcp_after_update_pricing', function( productId, GWConditionalPricing ) {

	var basePrice = GWConditionalPricing.getBasePrice( productId );
	if ( ! basePrice ) {
		return;
	}

	var $input = $( '#input_{0}_{1}'.format( GWConditionalPricing._formId, productId ) );
	if ( ! $input.length ) {
		return;
	}

	var $basePrice = $( '#base_price_{0}_{1}'.format( GWConditionalPricing._formId, productId ) );

	// Remove base price if there is no discounted price.
	if ( $input.text() === basePrice ) {
		$basePrice.remove();
	}
	// Otherwise, add base price if it has not been added.
	else if ( ! $basePrice.length ) {
		$basePrice = '<span id="base_price_{0}_{1}" style="text-decoration:line-through;margin-right:0.3rem">{2}</span>'.format( GWConditionalPricing._formId, productId, basePrice );
		$input.before( $basePrice );
	}

} );