Bavaria: Stamps

Hugh, you can use the "Postmark database" from the site "stampsx.com"
I found something similar:

This evening, I'm puzzling my way through another Bavarian Cover. 

A tiny letter being sent to Gefrees -- a town about 20KM north of Bayreuth.

At first glance it looks like it was posted from Bayreuth. There is a well struck half-circle postmark from Bayreuth dated October 11.

In the upper right corner there is a 3kr Bavarian Stamp. It's rose coloured and was issued on October 1, 1862 (Mi.Nr. 9). Use of the stamp was allowed until December 31, 1869. So the cover was mailed sometime during that period. 

So far, so good. But, the stamp has been obliterated with a Mill-Wheel cancel with a very legible '37' ... 37, according to my sources, is the number assigned to Buchloe in the south of Bavaria. Bayreuth's number is 23. So, unless my source is wrong, what gives? 

On the back, there are two more postmarks. One looks like the arrival cancel for Gefrees - a single ring cancel also dated October 11.
.The other one is another half-circle cancel also dated on October 11. It reads MKT.SCHORGAST. [Edit: Marktschorgast ... thanks franoise ] The Schorgast River is near Gefrees. I assume, therefore, it's a transit stamp that was applied as the cover got close to the destinateion. [Edit: Yes, it would have travelled 20 KM north from Bayreuth to Marktschorgast, then 6KM east to Gefrees]

The 3Kr rate make sense and arriving on the same day it was posted makes sense. And, the Gefrees arrival cancels on the back make sense.

But, I'm puzzeled by the postmarks on the front.

Did this cover originate in Buchloe and travel ~250KM north to Gefrees via Bayreuth where the half-circle cancel was applied?
Or
Did it originate in Bayreuth and travel 20KM north to Gefrees ... and somehow an incorrect numbered cancel was used on the stamp?

Or, is my information incorrect and 37 is OK and was indeed used in Bayreuth? [Edit: Yes, Bayreuth's number was 23 until 1856, then it changed to 37. Thanks franoise and rod222 ]

I'm probably overthinking this ... any corrections or suggestion are welcome.

Hi Hugh

You are correct,  BUT,  those Millwheels you have are only valid till 1856   (Bayreuth was then Numeral 23)

Bavaria - mill wheel stamp, 1st distribution
valid from August 1, 1850 to November 20, 1856
Source:
Beck/Holzschuher: The Bavarian mill wheel stamps, Munich 1911
All information is provided without guarantee - this wealth of data contains typographical errors
cannot be ruled out despite all care.

Stamps used from the beginning (August 1, 1850).

1 Abensberg
2 Aibling
3 Aichach
4 Allersberg
5 Alsenz
6 Altdorf
7 Altötting
8 Amberg
9 Amorbach
10 Ampfing
11 Annweiler
12 Ansbach
13 Arnstein
14 Aschaffenburg
15 Au near Landshut (Lower Bavaria)
16 Au near Munich (Upper Bavaria)
17 Aug
18 Augsburg
19 Baiersdorf20 Bamberg
21 Baunach
22 Bayerdiessen (now Diessen)
23 Bayreuth
24 Beilgries
25 Benediktbeuren
26 Berching
27 Berchtesgaden
28 mountain zabern
29 Berneck
30 Bischofsheim
31 blown box
32 Bobingen
33 Böhl
34 Breitengüssbach
35 Bruchmühlbach
36 Brückenau
37 Buchloe

franoise rod222 ...

Thanks. I knew that new numbers were added but I didn't realize that the older assigned numbers could change. I'll update my records.

rod222 regarding that lovely cover from Bavaria, I’m confused. This seem to be a highly franked item for a letter to Furth, that and the endorsement to Angleterre, England.

Another nice new addition to my collection, the Bayern 6 kreuzer blue, MiNr. 10, from 1861: