Nie wiem czemu ale mając np taką strukture:

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CREATE TABLE `citizenships` (
	`id_citizenships` INT(11) UNSIGNED NOT NULL AUTO_INCREMENT,
	`citizenships_name` VARCHAR(255) NOT NULL,
	`created_at` TIMESTAMP NULL DEFAULT NULL,
	`updated_at` TIMESTAMP NULL DEFAULT NULL,
	`deleted_at` TIMESTAMP NULL DEFAULT NULL,
	PRIMARY KEY (`id_citizenships`)
)
COLLATE='utf8_general_ci'
ENGINE=InnoDB
AUTO_INCREMENT=9
;
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i wywołując taki trigger:

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BEGIN
 
                IF (@user_id IS NULL ) THEN
                SET @user_id=0;
                END IF;
 
IF OLD.citizenships_name <> NEW.citizenships_name THEN
                INSERT INTO logs (user_id,object,object_field,object_id,new_value,old_value,message,STATUS,date) VALUES (@user_id,'citizenships','citizenships_name',OLD.id_citizenships,NEW.citizenships_name,OLD.citizenships_name,'Zmieniono nazw obywatelstwa','updated',NOW());
                END IF;
 
IF OLD.created_at <> NEW.created_at THEN
                INSERT INTO logs (user_id,object,object_field,object_id,new_value,old_value,message,STATUS,date) VALUES (@user_id,'citizenships','created_at',OLD.id_citizenships,NEW.created_at,OLD.created_at,'Zmieniono date dodania','updated',NOW());
                END IF;
 
IF OLD.updated_at <> NEW.updated_at THEN
                INSERT INTO logs (user_id,object,object_field,object_id,new_value,old_value,message,STATUS,date) VALUES (@user_id,'citizenships','updated_at',OLD.id_citizenships,NEW.updated_at,OLD.updated_at,'Zmieniono date aktualizacji','updated',NOW());
                END IF;
 
IF OLD.deleted_at <> NEW.deleted_at THEN
                INSERT INTO logs (user_id,object,object_field,object_id,new_value,old_value,message,STATUS,date) VALUES (@user_id,'citizenships','deleted_at',OLD.id_citizenships,NEW.deleted_at,OLD.deleted_at,'Zmieniono date usuniecia / usunieto rekANDd','updated',NOW());
                END IF;
 
                END
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Rekordy nie są dodawane do tabeli logs kiedy zmienane są wartości z NULL na timestamp. Jak już pole ma ustawiony timestamp i zmieniamy np o 1 minute do przodu itd. to rekordy się dodają ocb?

O warunku NULL<>'coś' nie możesz powiedzieć ani że jest prawdziwy, ani że jest fałszywy. Jest Null.
Zamień na np.
IF Coalesce(OLD.deleted_at, '2016-01-01')<>Coalesce(NEW.deleted_at, now()) THEN