ALTER TABLE `days`
    ADD COLUMN `is_active` TINYINT(1) NOT NULL DEFAULT 0 AFTER `release_time`,
    ADD COLUMN `activated_at` DATETIME NULL AFTER `is_active`,
    ADD COLUMN `manual_override` ENUM('auto','force_on','force_off') NOT NULL DEFAULT 'auto' AFTER `activated_at`;

UPDATE `days`
SET `is_active` = 1,
    `activated_at` = `release_time`
WHERE `release_time` <= UTC_TIMESTAMP();
