Complex sentence: For the next six years she worked in provincial companies (in particular York and at the Old Orchard Street Theatre in Bath), gradually building up a reputation, and her next Drury Lane appearance, on 10 October 1782, could not have been more different.
Split into simpler sentences: For the next six years she worked in provincial companies, in particular York and Bath. Having gradually built up a reputation, her next Drury Lane appearance, on 10 October 1782, could not have been more different.