FLightR: Is it possible to modify the find.times.distribution function?

[captaingriz]

I'm analyzing some Veery migration data, and would like to estimate when each bird arrived in S. America (<12.5 degrees latitude, >-77 degrees longitude) using the find.times.distribution function from FLightR.

Index<-which(Result$Spatial$Grid[,2]<12.5 & Result$Spatial$Grid[,1]>-77)
Arrival.SouthAmerica<-find.times.distribution(Result,Index)
print(Arrival.SouthAmerica)

By default the function returns the 0.025, 0.25, 0.5, 0.75, and 0.975 quantiles. I have been unsuccessful at modifying the find.times.distribution function to return the 0.10 and 0.90 quantiles so that I can present 80% credible intervals. Has someone successfully modified this function for a similar purpose, and would be willing to share their code? Thanks everyone.