Beexaboy would probably know if this is an original B & D or the later Gretsch-made model. Another likely source of decent information might be Banjotrader.
This is, in fact, a tenor banjo. I suspect this is an original B & D from the late twenties or early thirties. Many of the Gretsch made models used a different tailpiece.
The pickguard is not from either factory.
If you remove the resonator (the back of the banjo, held on by thumbscrews) there should be a serial number inside, as well as other information. The serial number will tell more about when this was made than any other feature.
From your photos, I can tell that your banjo was made by the original Bacon banjo company in Groton Connecticut. Removing the resonator will reveal the serial number stamped on the dowelstick & the rim and help us give you the year of manufacture. I am going to guess 1929, but will confirm when I see the number.
This model Bacon banjo is a particularly good tenor banjo. they are consistently great sounding and well worth the $400 too $800 that may be necessary to get it in great playing shape.
And as you are new to the hangout, I will recommend that you always post your pictures directly to the forum. They come out bigger and you will get more quality comments. Thanks to Emiel for doing that for you.
As mentioned above your B&D Serenader Silver Bell tenor banjo was built by the Bacon Banjo Company, Inc (incorporated 1921) at its factory on Thames Street in Groton, Conn. just across the Thames River from New London, Conn. Your banjo is a 1930's era banjo even though it was first introduced in the very late 20's. Attached is a ca. 1930 B&D Serenader catalog page and a photo of the factory. The "owner" of the company was Fred. J. Bacon a renowned 5-string banjoist (the "B" in B&D) and the general manager of the firm was David Day (the "D" in B&D). The B&D Serenader was the workhorse of the company's 1930's line, was well made as all Bacon's were, and was equipped with the company's latest Silver Bell tone ring. In those days and even now "Silver Bell" banjos commanded respect for their design and workmanship. The Bacon firm and the Serenader banjo soldiered on through the economically depressed 1930's until the factory was badly flood damaged on Sept. 21, 1938. Havoc from the depression combined with the flood caused the company to fail and the Bacon Banjo Company was sold to the Fred. Gretsch Manufacturing Co. in or about March 1940. Gretsch continued making B&D Serenader banjos 1940's-early 70's but as Bob Smakula noted above your banjo is one of the "originals" and much more sought after than the Gretsch copies. Demand for tenor banjos are in the doldrums these days and perhaps somewhat optimistic but my 2019 Vintage Guitar Price Guide for B&D Serenaders in excellent condition are listed at $1,350 - $1,750. Your banjo's handsomely done peghead, the original tailpiece and the pick-guard are certainly plusses in my book.
I have just found out on a Danish website that Polle passed away on the 19th of March 2021. Ed Britt passed away last February. I am very sorry to have asked this question, I must have missed it here on the Hangout.