When do you register music to P.R.O?

I worry about when should I register music to p.r.o.

Should I register all the music right away or after broadcast license is sold?

I wonder In which case can I collect the loyalty.
A) The user purchased a broadcast license yesterday. - I register that music to p.r.o today.
B) The user used music for broadcasting a year ago. - I register that music to p.r.o today.

(Sorry for my poor English.)

Register your music right away. Include your IPI number in the composer field and the ISWC on the description of the track. if the client is going to use your music in broadcast he should have all the information needed to fill the cue sheet properly. Is the only way to get royalties paid (as far as I know)

Thank you for answering!
I will try to register as much as I can.

I would like to know that royalty will be effective or not if I register after music is used.

Are you sure you want to abandon your post?