Colonial Era - Exchange Rates - Dollars And Shillings

I found this in the Hobart Town Gazette and Van Diemen's Land Advertiser, of Saturday 26 July 1823, at page 1 -

"Commissariat Office, July 24th, 1823
... The Spanish Dollar will be received, as formerly, at Five Shillings; the Colonial Dollar at Three-fourths; and the Dump at One-fourth:--"

Collectors of coins of that era will be aware that Spanish Dollars were, from time to time, overstruck or countermarked as English five-shilling pieces, so the exchange rate was well settled (although it varied a little over the years).

The point that surprised me was that the "Colonial Dollar", issued in NSW in 1813, and which we now call "the Holey Dollar", had been revalued according to the value of the silver it contained. I'm wondering when it ceased to be worth five shillings, at least in the Colonies ?