Based upon what I recall from looking at the stuff at Narou when this question came up over at [unnamed fan translation site someone with a name and avatar frighteningly similar to mine is associated with]...

The first 295 chapters of the WN were posted as R-15.
Starting with chapter 296, it shifted to the R-18 host site due to it having become obvious that was where it now belonged.
The R-15 site contains chapters 1-295.
The R-18 site starts with chapter 296.
It is one continuous work that starts in the R-15 and under site and then shifts over to the R-18 site.
There is no reboot.

The Official Licensed TL has been published through Volume 2 of the LN and Volume 6 of the Manga.
So far, the LN and WN are matching up pretty well, just slight edits.
Volume 3 of the LN looks to be where one should start watching to see if there really is any toning down between the WN and the LN.

So far, the reader speculation at [unnamed fan translation site] that they would diverge seems to be entirely based upon not grasping that the same skills existed in both versions, but had been given different English identifiers in the fan TL of the WN and the licensed TL of the LN; if you actually compared the status listings on a appearance by appearance basis, they really are the same skills.

Adding to the confusion is that while the translator for 7Seas stayed the same, the Editor and Proofreaders for the 7Seas LN changed between volumes 1 and 2 and this did seem to tie in with a number of identifiers changing between volumes; it could just be a coincidence and the translator decided at the volume break to change terms... but I find that hard to buy. The copyright/credits pages for the licensed LN translation confirm this.

Incidentally, the LN translator did a wondrous post concerning the joys of TLing Loner Life... read it here.

That's pretty much what I know.