My SP31 v1, purchased on Sep 2018 (both the flashlight and the invoice say SP31 without v2), has the same UI with 5 modes like the SP31 v2 but a XP-L2 HD led (the dome is quite noticeable). Runtime in medium is very high with a 3500mA Sanyo NCR18650GA. I had to stop the test after 11 hours because of a call, but the output (from ceilingbounce app) was at the same level as when started and the battery was still at 3.25V, impressive. In fact it even has the battery indicator. I guess at least a batch of the SP31 v1 was made with the v2 driver and battery indicator.