The 1 based 757 will be flying on a wed but will only be flying the morning upto now, so the RHO fits in nicely in the afternoon, if you can get the flight number it is easy to tell if its chartered. Most NCL flight numbers are LS5XX (except LGW which are the old Dan Air numbers, LS101-108)
A charter is usually LS2XXX or LS6XXXX