We accept 44khz at 16 bit stereo and up to 96khz 24 bit (WAV, FLAC, AIFF). Partners such as download or streaming providers generally only accept 44khz at 16 bit stereo thus, any format above that is mainly for your own preference.
To master your material we do not need a UPC or ISRC. That is only necessary for Distribution and Publishing aspects of which, if you use our distribution services we can provide those/or you can use your own.
More information on what our in-house mastering engineer does with your premasters can be found here - http://symphonicdistribution.com/comprehensive-mastering/