I was so worried that I went back after biometrics although we very few who experienced this change most ppl stay on “IP2” thru out.

Topsmamen:
This should be helpful to post-AOR folks.....

IRCC has introduced a number of changes in recent months and it is time to update our understanding of the post-AOR stages. This is simply built on the amazing work of an individual who developed an explanation of the various stages we can use - informally - to track the progress of our application. Other expert individuals have posited the underlying trends and found evidence for them. In short, the traditional transition from IP1 to IP2 to ghost update to PPR still holds but in a modified way due to these changes.

From 31st December 2018, everyone except for Inland candidates has to provide their biometrics which means the default starting stage applicants will see for their Background Check is ‘IP2’ (“We are processing your background check…”), however, this is a ‘False IP2’, meaning an IP2 that has appeared before it is actually due as the application has not in fact progressed to the IP2 stage yet.

If you have an AOR of 31st December 2018 or later, follow the chart below to track your progress. Candidates will remain in a state of 'False IP2' throughout their application and only see a series of 'ghost updates' following their MEP; the first such ghost update (which should follow shortly after MEP) will signify your Real IP1, the second ghost update will signify your Real IP2, and the third will be your ‘Final’ Ghost Update, following which you are likely to receive your PPR.

If you have an AOR date of up to 30 Dec 2018, the chart also applies to you if you meet one or more of these conditions: you are a CEC or PNP-Inland candidate, you were required to provide your biometrics or you did not pay your RPRF upfront.

Note for FSW-Outland candidates who have an AOR date of up to 30 Dec 2018: If you did not need to provide biometrics and paid your RPRF upfront, the old transition from NA1 all the way to a Final Ghost Update will still apply to you. Your Background Check should have started in NA1 ("Not Applicable" 1), meaning your Background Check status said "Not Applicable" right after you submitted your application.

Post-submission stages:
False IP2 - Usually right from AOR or just after MEP. Background Check shows "We are processing your background check. We will send you a message if we need more information.”
MEP - Medicals passed: review of medical results changes from "You do not need a medical exam." to "You have passed the medical exam." There might be no email for MEP.
Ghost Update - When you log in, the application says it's been "updated" but none of the fields have changed. Once you logout and log back in, the application returns to being "submitted". Ghost updates are not announced by email and a candidate must check their profile daily to not miss them.
Ghost Update #1 or Real IP1 - "In progress" 1: Background Check changes to "Your application is in progress. We will send you a message when we start your background check." Usually follows MEP. Some applicants (especially Inland and CEC) skip this stage. You should receive an email for your Real IP1 - the email will not provide any details, just that your application has been updated.
NA2 - "Not Applicable" 2: Background Check changes to "Not Applicable" again after IP1. Some applicants skip this stage and it is easily missed. No email.
Ghost Update #2 or Real IP2 - "In progress" 2: Background Check changes to "We are processing your background check. We will send you a message if we need more information." No email.
NA3 - "Not Applicable" 3: Background Check changes to "Not Applicable" again after IP2 (uncommon).
Ghost Update #3 or Final Ghost Update - Often considered a sign that PPR is coming soon. Not seen by all applicants.
PPR - Passport request: IRCC sends "Ready for visa" e-mail asking you to submit your documents to your visa office so they can issue your CoPR and entry visa if applicable. A PPR is announced only by email, and there may be no changes made directly to the profile. If you are worried you might miss it, you can whitelist the email domain @cic.gc.ca to ensure the email comes straight to your inbox.

It is likely some things may have been missed out but remember that these are not "official" stages, but they are used frequently throughout the forum to track the processing of applications.

Edited.....

Source: https://www.canadavisa.com/canada-immigration-discussion-board/threads/application-stages-what-they-mean-mep-ip1-ip2-ghost-update-version-2019.612656/