Evaluation of 2018 Audi S4 Premium Plus Lease

So I got quoted what I think is a pretty decent deal on a new Audi S4, but I figured I’d have the experts give me their thoughts:

Lease Term - 36 Months
Lease Miles - 12,000/ year
MSRP: $61200
Cap Cost after incentives/rebates: $50356 ($2500 Lease bonus + $1000.00 loyalty bonus)
DAS: $0.00
Monthly Payment: $661.21

Also, dealer is offering to essentially pay the residual on my existing vehicle, but roll in the 7 remaining payments. Current vehicle is a 2016 A3 2.0T Quattro with a payoff of ~$24k and 36month residual of ~$21k.

Is this a good idea or should I try to sell separately?

Thanks in advance!

Are we really supposed to answer this without know what vehicle it is and what the current buyout is?

Sorry about that; updated the OP!