PHP 7.4 warning: Array and string offset access syntax with curly braces (version 5).

[VladimirAus]

Deprecated function: Array and string offset access syntax with curly braces is deprecated in require_once() (line 4 of vendor/campaignmonitor/createsend-php/class/serialisation.php).

Version: 5.1.3

[markdavies]

I'm also seeing this in 5.1.3. I'm managing to get around it by prefixing method calls with '@' but that's obviously not ideal.

[contika]

I am getting this error:
production.ERROR: Array and string offset access syntax with curly braces is deprecated {"exception":"[object] (ErrorException(code: 0): Array and string offset access syntax with curly braces is deprecated at ...../vendor/campaignmonitor/createsend-php/class/services_json.php:156

[rvanbaalen]

This seems to have been resolved in the latest version with PR #102