I think that if they do the job right then being "late to the party" is not necessarily a bad thing. The xhp35 is a very different animal than xp-l and most especially when it comes to squeezing it into a single cell form factor. The amount of amps required from a single battery in order to power a boost driver for the xhp-35 is in no way comparable to the ease with which an xp-l can be driven. This is why I've seen a lot of chatter in the forums about people seeking out the "right cell" for their EC60 after the light already came with a supposed high drain Acebeam cell but just not high drain enough as it turns out. Also heat of course is much greater with xhp-35.
I think that if Olight comes out with a 1x 26650 xhp35 light and is representative of past build quality from Olight, and they push the envelop for powering the xhp35 then they would mop the floor with such a release. However there are a lot of little things involved for them. For instance, Olight likes to include a proprietary rechargeable 26650 with their lights and this may mean converting one of the highest output high drains into this Olight form factor. Just one of those things. If Olight comes out with a good xhp35 single cell or multi cell light then it should hopefully be worth the wait.