Thanks for all the replies. I must admit I'm a bit confused by some of them, particularly because I am relatively new to the whole timeshare business. I can only tell my experience, as it is only from there that I derive my understanding.
I purchased my VOI in Westin Aventuras in October 2020, in an office located in the Baja Point complex, after having toured one unit that was located in the Baja Point complex. No representation of any distinction between the two locations was ever made to me. Last year I stayed at Baja Point where I was greeted as a new owner. However, due to last year's peculiar travel situation, I was able to make that reservation only a few weeks in advance, so the issue of the home reservation period did not occur. This is just to say that at no point I was given any info that even remotely made me doubt that Baja Point was part of my home resort. If anything, I might have suspected that the hotel building wasn't, as all the prospective buyers were transported from the hotel to Baja Point to attend the sale presentation.
I just re-read my contract and, as it likely comes as no surprise to anyone, the definition of the home resort is very much a gray zone one. Here is what it says:
"
Hoteles Cabos K22.5 ("Hoteles Cabo" and/or "Trust Association Manager") has established a Timeshare Regime ("Regime'") covering one hundred and forty six (146) vacation units ("Vacation Units") which are subject to the Rules and Regulations of the Regime, and are located within a parcel of property described as Unit "A" Private Unit One (Hotel) (Hotel Unit") which is part of the Condominio Westin Regina Los Cabos, located at Carretera Transpeninsular KM. 22.5 SN Baja California Sur, Los Cabos San Jose del Cabo. Cerro Colorado, CP 23400, Mexico. The Hotel Unit is further known as the Westin Los Cabos Resort Villas and Spa."
I now see how the definition
Unit "A" Private Unit One (Hotel) (Hotel Unit") might possibly be the hidden clue for someone with a better lawyerly eyes than mine, to which it was further clouded by the qualifier
which is part of the Condominio Westin Regina Los Cabos, which as some noticed was the previous name of Baja Point.
Besides the contract legalese and its non-conformity with the more or less honest representations made during a sale pitch, there are still a few things that I do not understand. If Baja Point is not part of Westin Aventuras, as alexadeparis and dioxide45 state, this should imply that is an autonomous entity, separated from the Westin Los Cabos Resort Villas and Spa. However, it is not an independent resort that can be queried for availabilty, because it does not show up among the choices in the Destinations menu on the Vistana website (screenshot attached). The only way to verify availability at Baja Point is by selecting Westin Los Cabos Resort Villas and Spa, under which umbrella its available accomodation are shown, as it can be seen in the screenshot attached to my original post. So if it is part of the Westin Los Cabos Resort Villas and Spa, how can it not be part of Westin Aventuras? As a mathematician, this deeply disturbs me, as it goes against all the fundamental laws of set theory ;-)
My hypothesis is that there is an ongoing sneaky project to separate Baja Point from Westin Los Cabos, and hence from Aventuras, basically disenfranchising those who, like me, bought mostly because of it. My main reason to post, was to verify my suspicion that this is something new, checking if anyone had some past experience in which it was clear that Baja Point was not part of the Aventuras home resort.