Abstract: 
We consider the compressible OldroydB model derived in the paper {\em Existence of largedata finiteenergy global weak solutions to a compressible OldroydB model}, Comm. Math. Sci. 15 (2017), 12651323 by J. W. Barrett, Y. Lu and E. S\"uli, where the existence of globalintime finiteenergy weak solutions was shown in two dimensional setting. In this paper, we first state a local wellposedness result for this compressible OldroydB model. In two dimensional setting, we give a (refined) blowup criterion involving only the upper bound of the fluid density. We then show that, if the initial fluid density and polymer number density admit a positive lower bound, the weak solution coincides with the strong one as long as the latter exists. Moreover, if the fluid density of a weak solution issued from regular initial data admits a finite upper bound, this weak solution is indeed a strong one; this can be seen as a corollary of the refined blowup criterion and the weakstrong uniqueness. 
