Just an update:
I was on the phone with CIC and they told me that this is, indeed AIP - which concludes Step 1 of the application.
We are now entering step 2 - Final Decision "After receiving the approval in principle letter, medical, security and background checks have to be done for the sponsored person and their family members, if applicable. After all the requirements have been met, a final decision is reached and the file is sent to the local office (unless it is already there). The local office will then contact the sponsored person to give them an appointment so they can become a permanent resident of Canada. The processing time for this step varies depending on the case."
Thank you so much for all your help! Appreciate it!