That doesn't mean it's necessarily been in use since 2015 as it could easily have sat in storage or a shipping container for several years. (Looks like December 2015, unit 00218, with area codes - sounds about right considering the Leixen manufacturers state up to 50,000 units production capacity per run.) The following number could well be a design/manufacture date of 21st November 2015 and the serial number made up in a similar fashion. The board markings look like 'QZ' - QuanZhou Leixen as the designer or manufacturer, '6666' obviously the model and 'PCB1' being the first version printed circuit board design. (Wouldn't surprise me if the earlier units could go down to the 12m band but limited via firmware/software which has been through a few revisions.)
The latter V.4 I believe doesn't have that jumper and can be set by a simple button press/power on combo for 'export' mode. I don't think they changed much, (without access to a schematic), apart from apparent frequency range which on the earlier radios was supposedly limited and had a 'export' jumper on the board. Don't know for sure Ray never having one but they do look like a generic design - CRT SS9900 / Dynascan 10M66 etc.
