Update README.md

Added note regarding v1.1 hardware

README.md

@@ -58,14 +58,18 @@ You can watch the videos of the *Temporarily Offline* and *HAM RADIO DUDE* YouTu
 This gives you 5 (or more) SMD assembled AIOC. The only thing left to do is soldering on the TRS connectors (see [here](#how-to-assemble)).
 The total bill should be around 60$ US for 5 pieces plus tax and shipping from China.
 
-Note that the following message from JLCPCB is okay and can be ignored.
+__Note__ that the following message from JLCPCB is okay and can be ignored.
 ````
 The below parts won't be assembled due to data missing.
 H1,H2 designators don't exist in the BOM file.
 J2,D3,D4,R17 designators don't exist in the CPL file.
 ````
 
-Note for people doing their own PCB production: I suggest using the LCSC part numbers in the BOM file as a guide on what to buy (especially regarding the MCU).
+__Note__ for people doing their own PCB production: I suggest using the LCSC part numbers in the BOM file as a guide on what to buy (especially regarding the MCU).
+
+__Note__ the current hardware version is **1.0**, but there is a pre-release **1.1** available [here](https://github.com/skuep/AIOC/tree/k1-aioc-rev1.1) that features
+- support for an external hardware input (e.g. for COS)
+- a split pad for the PTT/UART contact, so in case you would like to use the AIOC hardware for another purpose than a K1-style connector, you can separate these two signals that are otherwise connected to the same TRS contact.
 
 ## How To Assemble
 This is the process I use for building. See photographs in ``images`` folder.