How can I set TIMESTAMP's default to future date?
Use a trigger:

mysql&gt; CREATE TRIGGER dateinsert BEFORE INSERT ON testtable
    -&gt; FOR EACH ROW
    -&gt; SET NEW.yourdate =  DATE_ADD(CURRENT_TIMESTAMP(),INTERVAL 10 DAY);
Query OK, 0 rows affected (0.00 sec)

mysql&gt; insert into testtable (blah) values (1);
Query OK, 1 row affected (0.00 sec)

mysql&gt; select * from testtable;
+------+------------+
| blah | yourdate   |
+------+------------+
|    1 | 2016-07-25 |
+------+------------+
1 row in set (0.00 sec)

mysql&gt;