Van Diemen's land : an operatic drama, in three acts / by W. T. Moncrieff,
Esq. author of Monsieur Tonson...&c. ; printed from the acting copy, with remarks,
biographical and critical...

Publication date [18--?]
Publisher London : John Cumberland, 2, Cumberland Terrace, Camden New Town [London]


See here: https://archive.org/details/vandiemenslandop0000monc/page/72/mode/2up?q=%22landlady+proves+kind+to+me%22


Although not dated, the play would have been performed a year or two before appearing in the Australian newspaper.

So this gets this fragment in the play to 1829 or 1830.