It seems that each time Rockstar holds a generous promotion to give back to the players of Grand Theft Auto Online, something goes wrong on the technical side of things. In the past, prior events to hand out in-game currency haven't occurred on time, sometimes people don't receive anything (while others get it multiple times) and even once, players were charged for a "free" car.
Rockstar currently has multiple irons in the fire, with a free GTA$ 250,000 bonus and 10% "tax rebate" scheduled to go out a few days from now, as well as a Shark Card purchase bonus which gets you more GTA$ for the same amount of cash and which is supposed to operate in real-time. Different card tiers get you different percentage bonuses, but it does make the prospect of buying into the microtransactions all the more enticing.
However, things have all gone bonkers.
A bunch of players are reporting strange money deposits from Rockstar in odd amounts, while others who should have received bonuses didn't. Making matters worse is other players who, upon seeing something was amiss started spreading false reports as well, for... whatever strange reason. We don't see what they stand to gain from this, as any attempt to rake in cash from Rockstar Support based on false claims won't work.
Some players who haven't bought a single Shark Card at all have reported receiving GTA$ 200,000, some even multiple times. This doesn't line up with the free cash bonus, nor does it line up with any of the percentage bonuses off Shark Cards. Others have received GTA$ 400,000. Some Shark Card buyers have received duplicate bonus top-ups (which isn't bad, of course) while others haven't received any bonuses. Other reports include odd numbers like GTA$ 500,000, GTA$ 400,000, GTA$ 675,000 and some go up to several million.
Some of the more absurd reports, which are likely the result of Shark Card whaling, show in-game screenshots of receiving 20 to 36 million in GTA$ from Rockstar. Now, GTA$ 36 million would be enough money for a lot of things in GTA Online, but no-one gets 36 million for free, just like that. None of the verified bugged payouts go even near that, and any glitch regulating this system is bound to be constrained within some logical numerical boundary.
Either way, previous $GTA distribution bugs have always been sorted out within a day or two in the past, so if you are yet to receive any bonus cash in spite of being applicable, be patient and you'll get your due. On that note, if you've only qualified for the GTA$ 250,000 and 10% rebate, don't be worried if you haven't gotten anything yet, as those payouts will come in waves and haven't begun yet.
Just don't get your hopes up about being accidentally laden with tens of millions because of this bug - that just won't happen.