ABI guarantee for auditd

Hi, Sorry for the deluge of questions :) Regarding auditd, what is the ABI guarantee ? Do you guarantee that the text contained in audit_reply->msg.data will always be the same format ? I imagine you reserve the right to add fields, but how about removing any or even reordering them ? Or are people simply required to use auparse to guarantee they get records properly ? Also, regarding 'unofficial' ABI compatibility, when has the audit_reply->msg.data format changed last ? Say these past 3-4 years, were there any changes in the format or could I use a faster, but specifically focused parser on the msgs when detecting older releases at least ? Thanks, Hassan