Change Section Headers Per Campaign

/**

 * Change the section headers in the donation form.

 *

 * @param  array $fields All the donation form fields.

 * @return array

 */

function ed_charitable_change_donation_form_section_headers_per_campaign( $fields, $form ) {

	if ( 123 === $form->get_campaign()->ID ) {

		// Section headers for the donation form for campaign #123.

		$fields['donation_fields']['legend'] = 'Custom Choose Your Donation Amount';

		$fields['details_fields']['legend'] = 'Custom Your Information';

		$fields['payment_fields']['legend'] = 'Custom Payment Information';

	} else {

		// Section headers for all other campaigns' donation forms.

		$fields['donation_fields']['legend'] = 'Choose Your Donation Amount';

		$fields['details_fields']['legend'] = 'Your Information';

		$fields['payment_fields']['legend'] = 'Payment Information';

	}

	// Finally, return the modified fields array.

	return $fields;

}

add_filter( 'charitable_donation_form_fields', 'ed_charitable_change_donation_form_section_headers_per_campaign', 20, 2 );