Thanks. I assume they move around to evade the Chinese jammers? (which were not propagating here, if they were on)
p.s. They are on 11507 right now, 1218z, again with fair reception, SIO 322. Obviously I don't understand what they're saying, but the musical interludes sound Tibetan.
15533 at 1230z.
15547 at 1245z.
That's one of those things that is always cause for concern, when it comes to logging stations China might be jamming. In my experience, their jamming is so overwhelming that usually that's what we're copying. CNR1 is their main jammer. They don't use the Firedrake nearly as often.
I figured this out over the summer trying to listen to Radio Taiwan International. They have an English broadcast 1100-1200 UTC on 7445 kHz, followed by a Mandarin one starting at 1200. I got some decent copies of the English broadcast, which isn't jammed, but once 1200 rolled around, all of a sudden this huge signal came on. Did they boost their signal? Not according to any online schedule I could see, which all report that they maintain the same signal strength and azimuth. (Unfortunately not in the HFCC schedule, since they don't participate.) I tuned over to a scheduled CNR1 broadcast and found out that CNR1 was now jamming RTI. It's kind of fun to watch on the waterfall when it happens. (This time of year, Asia is getting harder to copy in the morning, at least where I am, and that RTI English broadcast is little more than a het now.)
Since then, any time I come across something reported as being jammed (the eibi schedule is best for reporting that, as they always list "CNR1 jammer/Firedrake" against any non-PRC broadcast in Mandarin, Cantonese, or Tibetan aimed at China), I try to find an actual official CNR1 broadcast to compare. I've yet to find that I was copying the other station, although sometimes in the case of those transmitting from Palau, I can hear them along with the jamming.
Tl;dr - without a recognizable interval or station ID, it's safer to assume that you're copying CNR1 than another station.
I'm not saying that you didn't hear Voice of Tibet, btw. I'm posting this primarily because I see a lot of people reporting that they're hearing this or that, without indicating how they determined it aside from checking a schedule.