I have scans of some Monthly Army Lists for 1813 (& other years). They show:
Capt H.M. Clune 5 Aug 1804
Lt. Rich Blake 5 Mar 1807
The dates are that of their rank in the regiment.
Clune has an "s" by his name which I think indicates he was on the Staff up until Sept 1813 when he appears to be back with the regiment.
Blake is with regiment except for month of Aug 1813 when he has a "d" by his name indicating he was detatched.
Hope this helps.