Deprecated error messages

Hi,

I am doing some investigation to integrate Chargify with WordPress and come across this plugin that looks to do exactly what I need. I am running the twenty seventeen theme and installed the plugin on my localhost (MAMP PHP 7.1.1). I get a lot of errors. Is this something that will be updated?

Deprecated: Non-static method chargify::subscriptionRedirect() should not be called statically in /Applications/MAMP/htdocs/wordpress-play/wp-includes/class-wp-hook.php on line 298

Deprecated: Non-static method chargify::subscriptionPost() should not be called statically in /Applications/MAMP/htdocs/wordpress-play/wp-includes/class-wp-hook.php on line 298

Deprecated: Non-static method chargify::subscriptionCreate() should not be called statically in /Applications/MAMP/htdocs/wordpress-play/wp-includes/class-wp-hook.php on line 298

Deprecated: Non-static method chargify::control() should not be called statically in /Applications/MAMP/htdocs/wordpress-play/wp-includes/class-wp-hook.php on line 298

Deprecated: Non-static method chargify::createMetaAccessBox() should not be called statically in /Applications/MAMP/htdocs/wordpress-play/wp-includes/class-wp-hook.php on line 298

Warning: Cannot modify header information – headers already sent by (output started at /Applications/MAMP/htdocs/wordpress-play/wp-includes/class-wp-hook.php:298) in /Applications/MAMP/htdocs/wordpress-play/wp-includes/pluggable.php on line 1210

Thank you

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