When sugar substituted cpd is acid hydrolysed for the determination of absolute configuration, will the sugars that are recovered retain pyranose / furanose form or will it be recovered as open chain structured sugar?

The sugar will take the cyclic form they prefer in the solution in which they are found; pyranose or furanose but not the open chain, there is VERY little of that.
I am not familiar with the configuration determination of which you speak. Can you tell more about it or provide a reference?