update to add a link to sapphire lens
I was able to purchase a new 2020 RRT-01 driver from info@jetbeamlight.com
the new driver has strobe.
But the 2020 drivers vary, some dont start at the lowest mode, although it works to dial down after a brighter start. Some 2020 drivers have visible flicker on the lowest modes. And some have high parasitic drain.
I went to a 219b 4500k 9080 sw45k and now get 400 lumens momentary maximum.
To use 219b or 519a requires a new mcpcb and either file down a 16mm noctigon to about 15mm , or source something smaller, such as this (and reflow a Nichia LED):
I also replaced the reflector and now have a much nicer, ring free spill and tighter hotspot
there are two reflector choices, thanks to research by moderator007
Reflector #1 . I like the very tight hotspot and smooth ringless spill
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Reflector #2
(I like this one slightly better, the hotspot is a bit larger but without the “donut hole” in the middle of the hotspot)
here is a centering ring for reflector 1 or 2
try both 
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IF you decide to change the Control ring grease:
I like Nyogel 767a. Do not try to open the control ring unless the mcpcb and driver are removed first.