It's hard to pinpoint - unless you were there when it happened. I was not. I don't think there is a clear and definitive numbering schema change that can be identified as the dividing line. There are some members here that have more close ties with former employees, and the politics of the end of Bob's participation at Carver Corp.
To my knowledge, he left just before the TFM-75 was launched..., and it's design is largely Bob's, but had to be "finished" and delivered by his engineering team that he built..., so his finger prints are on that amp. Over the next many months..., Bob started Sunfire, while the people that took over Carver Corp ran it into the ground. The assets and designs for amps and such were sold to an organization called Phoenix Gold, that produced more pro amps... using the brand Carver, and many of the core designs. You'll find some amps were "re-launched" with some changes over those that were launched during the time Bob Carver was at Carver Corp..., like for example, the TFM-35 and TFM-55 amps. That latter amp is more rare, both are highly coveted. Post-Bob-Carver, they were redesigned adding THX technology for movie sound reproduction to meat the THX theater sound specification. The latter versions of these amps lost their gain control (on the front face) and to many, were harder to work on because the chassis design was changed so that the bottom panel did not reveal the board..., making disassembly necessary to work on and service the amps. The later versions were branded model "TFM-35x" and "TFM-55x." They are still very respectable. And have Bob Carver's legacy in them from their ancestor, but are different. That is just one example that sticks in my limited memory.
I don't have a specific time-line of what were Carver designs, and what were post-Carver designs. Others may pipe up with more data. We (generally speaking) as members of the site, like the earlier amps and preamps. (Many of the other components, CD players, etc. were outsourced to Japanese makers - still good). Later, much later, there were some Chinese-made integrated amps as the owners of the brand tried to cut costs and meet needs of a changing consumer retail market - like the 1090, 1050 and 1020, less common - but look like Carver branded gear.
Wish I could be more helpful ...and I may have some of the above wrong, too - I just don't have the historical data to answer your question, and the separation occurred before the Internet was the force it is to document things like this in real time..., It is pretty cool that Bob published much of the documentation on the amps he designed into the public domain... There's a VAST library here on the site that has been collected over the years - but alas, the site just migrated to a new host/platform and that section of the site is still under construction.
Stick around on this site as people share new stories and read the past threads, and over time, you will pick up a lot of this folklore and stories that shape our perspectives on the bits of wisdom and history that do exist!