Congrats on your approval!
I'll respectfully disagree with everyone that has said that the card is not bucketed based on the $2000 SL. While I'm not saying that it is bucketed, SL in and of itself is not the only way to know if a CO card is bucketed. The best way to know if a card is going to be bucketed IMO depends upon your profile at the time of approval for a CO product. My question then to the OP is what did your profile look like? What are your Fico scores for example and what was the score you were provided with at the time of your approval? What else can you tell us about your profile such as clean/dirty, thick/thin, young/old etc?
I offer myself and personal experience on this subject as an example. I was approved for a Capital One Platinum card with a $3000 limit, but it was indeed a bucketed card. Even with heavy use/PIF for several years it was next to impossible to grow it.
On the surface it would have appeared that a $3000 SL wouldn't be bucketed, but based on my overall profile it indeed was. Why? Well, I was approved with a 619 score. My file however was aged (15 years or so) and thick (probably 20 accounts) but was recently dirty. My file had been clean for ever a decade and recently had negative information introduced, dropping my ~800 scores down to the low 600s. Capital One was my first rebuild card. My opinion on the relatively high SL for the starter card was simply because my file overall was strong, but it was still bucketed due to the recent negative information on my file.
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