Complex sentence: Advenza operated using Class 47, two Class 57s, and Class 66 locomotives; four former Direct Rail Services (DRS) Class 66/4 locomotives (66406 to 66409) and reclassified as subtype 66/8 with numbers 66-840 to 66-843.
Split into simpler sentences: Advenza operated using Class 47, two Class 57s, and four Class 66 locomotives. Four former Direct Rail Services (DRS) Class 66/4 locomotives (66406 to 66409) and reclassified as subtype 66/8 with numbers 66-840 to 66-843.