Were the Chelsea pensioners simply filling a limited role rather than Anson's requested soldier allocation?
Short answerThey were the Army's answer to his request for 500 soldiers; only about half of the assigned men actually embarked.
NotesThe Army assigned 500 men from Chelsea Hospital against Anson's request for 500 soldiers. This was the soldier allocation itself, despite the audience's understanding that the pensioners had a more limited role. Only about half embarked, with the closing estimate given as roughly 240.