Complex sentence: They do their basic 14-week military training at the Army Training Centre Pirbright and their 27-week special-to-arm training at Templer Training Delivery Wing, Chicksands, at the end of which they are promoted to Lance Corporal.
Split into simpler sentences: They do their basic 14-week military training at the Army Training Centre Pirbright. OPMI will complete their 27-week special-to-arm training at Templer Training Delivery Wing, Chicksands, at the end of which they are promoted to Lance Corporal.