I am trying to understand the CTR DRBG specification in NIST SP 800-90A. It seems slightly different to a pure stream cipher in that the key and counter are reset after each generate call using the output pseudo-random bits. I understand that this is to provide backtracking resistance.
My question is, does this imply that the output bits produced by the DRBG are dependent on how the requests are 'chunked'? i.e.
$$ Generate(state, 8) || Generate(state, 12) \neq Generate(state, 12) || Generate(state, 8) $$
...or have I not understood the specification correctly.