Outlook.exe /CleanRules - what *Specifically* does this do?

Hi All,

TL,DR:
How specifically does the "outlook.exe /cleanrules" CMD Switch actually go about "starting Outlook and deleting all Server and Client-based Rules"?

Little bit of scene setting for the question.

The organisation I work for migrated from On-premises Exchange to Exchange Online over the last 2 years, completing earlier this year.

Periodically since then we get support tickets raised from Users advising when they turn their Automatic Replies (Out of Office) on people are either receiving 2 separate Out of Office Messages (one usually very outdated and not what they specifically setup in the Automatic Replies menu) and/or they get a Mail Undeliverable error when the message is attempted to be forwarded to a now defunct 3rd Party email service we also had and is now not used by us.

After investigation this was confirmed with Microsoft that this was a Microsoft Outlook Desktop Client based rule that had included itself in our migration data, activated itself and is now causing the issues described above.

Microsoft sent us a document to follow advising to download a tool called MFCMAPI which is a Super powerful if you know what you're doing with it in terms of what it can allow you to see/manage within an Outlook Mail Profile.

(It's also apparently Super dangerous apparently if you don't. Which is where the bulk of our 1st Line Support come in. Mail profiles to the level of Detail MFCMAPI shows and requires you to understand is not their area of expertise.)

(the initial guidance was linking to here - https://docs.microsoft.com/en-us/exchange/troubleshoot/administration/delete-junk-email-rules-mfcmapi-exchange ) but we were advised to look for and use the DELETE_HARD_DELETE(unrecoverable) option on the following 2 item types present in the window you reach after following step A- F in the provided guide:

We were advised to Hard Delete:
IPM.ExtendedRule.Message
IPM.Rule.Version2.Message

Wash, rinse, repeat for all affected users who raise a ticket and the problem is gone.

We're still seeing calls occasionally popup but I stumbled across an Outlook CMD Switch that should still be available;

Outlook.exe /cleanrules

The description of /cleanrules on the https://support.microsoft.com/en-us/office/command-line-switches-for-microsoft-office-products-079164cd-4ef5-4178-b235-441737deb3a6#Category=Outlook says this will "[Start] Outlook and deletes client- and server-based rules."

My question (finally, sorry!) is;

Does the /cleanrules switch do the equivalent of going through MFCMAPI and Hard Deleting the two categories of items that we've successfully resolved the fault with before?

If so this could provide us with a much cleaner fix than what has been sent to us previously without needing the [potentially!] terrifying MFCMAPI and the potential for someone to make a very easy-to-do error.

Thanks so much to everyone who bothers to read and reply to this - appreciate the patience.