Why am I not allowed on an open-grouped invoice record to change custom body or sublist field value on an invoice that is grouped, getting this error: FIELDS_1_CANNOT_BE_CHANGED_AFTER_INVOICE_IS_GROUPED so what are the implications when ungrouping ?

AI generated answer (using internal Slack threads):

The error message

FIELDS_1_CANNOT_BE_CHANGED_AFTER_INVOICE_IS_GROUPED

is thrown when you try to change custom body or sublist field value on an invoice that is grouped. This is because NetSuite restricts certain modifications to grouped invoices to maintain data integrity and consistency. When an invoice is grouped, it means that it is linked to other transactions (like a Sales Order) and changing certain fields could disrupt this link or cause inconsistencies in the data. Therefore, NetSuite prevents these changes from being made. As for the implications of ungrouping, when you ungroup an invoice, it is no longer linked to the other transactions in the group. This means that you can freely modify the fields that were previously restricted. However, you should be aware that this could lead to inconsistencies in your data if the invoice is not updated to reflect the changes made to the other transactions in the group. For example, if you ungroup an invoice and change the customer, the invoice will no longer match the Sales Order it was originally linked to. This could cause confusion or errors in your accounting records. Therefore, it's important to carefully consider the implications before ungrouping an invoice. ****** Disclaimer: This response was generated by an artificial intelligence assistant based on previous conversations from multiple Slack channels, and may contain inaccuracies or mistakes. ******