Estatik 2.4.0 and earlier versions do not allow to update without saving custom change. It means that if you have custom changes and need to update to the version 3.0 or higher, you will have to repeat customization or do not update.
Customers who have ver. 3.0 have no such problem and all customizations will be saved after every update.
If you have any questions or concerns regarding it, please contact us and we will reply all of them.