2015 Prius Cs - April discounts bringing down price to 16K for C1 (California only maybe?)

I'm in northern California and wanted to share the discounts I got on my new 2015 C1. Maybe this information will be helpful to anyone else in the market for one.

MSRP (on dealer's site): $20590
Dealer Discount (formerly on dealer's site): $2500
Factory Rebate: $1500 (applies regardless of whether or not you finance through TFS). This article mentions southern California getting a $2000 cash rebate, but the $2000 is without TFS financing. With TFS, the SoCal rebate is currently only $500.

The dealer wouldn't go any lower than the advertised web price of $16590 (I asked for $16000) but I think others could negotiate it lower than that.

A few factors that may be contributing to these discounts:
1. Lower gas prices (but for how long? ) that have stayed low for many months now resulting in more unsold Prii that would normally sell more when gas prices are higher.
2. Last year of Gen 3 means no more of them being produced - perhaps a reason to sell them for less?
3. Toyota might(?) be trying regain the yearly "Top Selling Car in California" title from the Honda Accord.

Strangely (and this is only a few hours later), the $2500 dealer discount is now missing from their website. Maybe some of you can find some of these details useful - would be interesting to see if others are getting similar or lower prices.