Fatal Error Upon Plugin Update

What time zone so your WordPress set for? (under Admin -> Settings -> General)

Also, what version of PHP are you using?

If you make a PHP file to show your server’s PHP info like so:

<?php

phpinfo();

Save that to your server and then view that PHP file through your browser (you can name it anything you want), you should find a section titled “date” and some info about the timezone database it’s using.

Normally the “Timezone Database” will be “internal” and you can see the Olson Timezone Database Version there. Can you tell me if your server is using the internal database and if so, what version it shows there?

Honestly I’m a little perplexed about what’s going on here because in *theory* that should never happen like you are seeing there (obviously it is though for some reason).

I don’t suppose upgrading PHP might be an option just to rule out some weird bug with the PHP DateTimeZone class in old versions? On a side note, PHP 5.4 was end of lifed a long time ago and doesn’t even get security updates in a long time now: http://php.net/supported-versions.php

If you add this line to your wp-config.php file (at the top or bottom, doesn’t matter where), does the error go away?

date_default_timezone_set('America/Vancouver');

It’s a little difficult to debug on this end because I don’t have any servers that I can put PHP 5.4 on it.

The “date.timezone” setting in your php.ini file is required when using timezone functions (the alternative if you can’t edit php.ini is to add the above line to your config file since it will at least set it on a per request basis).

From the PHP documentation, it looks like PHP 5.4 is the version that changed how it works (specifically prior to that PHP would be fine using the time zone as set by the server itself). Some info on that here:
http://php.net/manual/en/datetime.configuration.php#ini.date.timezone