While upgrading a user needs to fill in a form with a range of required data. Jelastic can be configured in order to customize this upgrade window for PBA and WHMCS systems.

The default upgrade window can be changed based on your requirements. There can be rearranged the order of the fields, deleted some of them or added any extra options. For example, to gather more details about user during upgrade you can add such custom fields as client type, Tax ID, citizenship ID, ID issue date, etc.
To configure these fields, follow the next steps:
1. Open JCA and navigate to the System settings menu item.

2. Enable Expert mode and expand jbilling parameter group.
Find account.convert.json.config parameter.

3. Edit the parameter value in order to customize the upgrade form for your users.

Here you can set adding new fields to the form, ordering the existing ones or specifying extra rules. Below we provide the details on the Value syntax of account.convert.json.config parameter due to each function available.