Can't restore a PERSISTENT column that uses DATE_FORMAT()

I’m in the process of moving to 10.2, starting with slaving to my operational master (10.1.12). So I dumped the master, and started a restore on the 10.2.2 slave.

But the restore fails with:

ERROR 1901 (HY000) at line 7140: Function or expression 'date_format()' cannot be used in the GENERATED ALWAYS AS clause of `start_day`

I use PERSISTENT columns with the day of the week next to date columns quite heavily. This particular one looks like:

CREATE TABLE `a_nuke_counts` (

  `time_start` timestamp NOT NULL DEFAULT '0000-00-00 00:00:00',

  `start_day` enum('Sun','Mon','Tue','Wed','Thu','Fri','Sat') AS (DATE_FORMAT(`time_start`, '%a')) PERSISTENT,

  `time_end` timestamp NOT NULL DEFAULT '0000-00-00 00:00:00',

  `end_day` enum('Sun','Mon','Tue','Wed','Thu','Fri','Sat') AS (DATE_FORMAT(`time_end`, '%a')) PERSISTENT,

  `count_start` int(10) unsigned NOT NULL,

  `count_end` int(10) unsigned NOT NULL,

  `location` enum('indoor','outdoor','paper sample') NOT NULL DEFAULT 'indoor',

  `note` varchar(255) NOT NULL

) ENGINE=MyISAM DEFAULT CHARSET=utf8;

but there are many more.

Should I simply be using VARCHAR(3) instead of ENUM for these? In this case, it's a bug that MDEV 10.1.12 allowed me define and use it as an ENUM.

(Please don’t tell me to use emacs on the 9.1GB dump…

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UPDATE: I just tried executing the above table schema, adding a few records, exporting, DROPping, and importing on MDEV 10.1.12, using Sequel Pro (Mac MySQL GUI). No problem. So it may be a problem with 10.2.2 only. Or perhaps mysqldump.