Exactly. I thought this is AIP as well initially, but looking at the letter, reading it over and over again and the refusals that happened to OP and some other students on this forum points to the fact that this letter is NOT AIP at all. It is pre-AIP of some kind. If you had 0% hope of getting an AIP before Sept 15, this makes it to 50%, that is the only purpose of this letter.. There are students who were outright refused in the preliminary eligibility stage, but this letter puts these students ahead of them at least BUT still not fully approved. Abu Dhabi is notorious for not approving visas for number of reasons, specially for TRV applications, students, visitors etc, that is why they still have the authority to refuse application even after this letter since the letter never mentioned Approval in Principle. I am also assuming now that there'll be rain of refusals in upcoming days. I really hope it changes to approval but, damn, this is rough.
This is specially not a good news for Pakistani students since they already have close to 81% refusal rate in past years (you can google and find data on it). SDS was suppose to make Canadian education lucrative for students but I guess, Covid happened and now everyone is in a mess now!