Typo but could be misleading:
In the Zap Channel Module's configuration file (zapata.conf), you can define groups of Zap channels that get treated as a single channel as far as the Dial command is concerned. You specify which of four methods the Zap channel module is to use to select a non-busy channel from the channel group by prefixing the group number with one of the letters g, G, r, or R:
g: select the lowest-numbered non-busy Zap channel.
G: select the highest-numbered non-busy Zap channel.
r: use a round-robin search, starting at the next highest channel than last time.
G: use a round-robin search, starting at the next lowest channel than last time.
Last uppercase "G" should be "R"