The 991-series Porsche 911 is getting a bit long in the tooth and due for replacement soon, as we've been tracking for close to two years.

Earlier this year, Porsche launched a GT2 RS which is normally the last core 911 member to be introduced. Now it looks like a Speedster version could be the final 991-series 911 to be unveiled.

According to CAR, Porsche is working on a limited-edition Speedster as a farewell for the 991-series. The automaker did the same for the previous-generation 997-series 911.

The Speedsters reconnect the 911 to the days of the 356. The cars tend to feature a chopped, raked windshield plus a double-bubble rear deck that lends an almost hump-like proportion to the 911. They also tend to come with retro features.

Should a new Speedster be launched, expect it to feature the pumped fenders of the Carrera 4 but with drive going to the rear wheels only. The spec, meanwhile, should match  that of the Carrera GTS, which would mean the car would come with a 3.0-liter twin-turbocharged flat-6 good for 450 horsepower and 405 pound-feet of torque.

Pricing is sure to be high, as this is a limited-edition 911 we're talking about, and possibly the last of the 991s. If indeed the Speedster is coming, it could arrive as early as next month’s 2017 Frankfurt auto show, and Motor Authority will be on hand for the unveiling. To learn about some of the other cars headed for the German show, head to our dedicated hub.