Lets pretend for a second that it's not that the artist is NOT getting paid for 3 months, but they (Apple) are delaying their payment for 3 months. The 3 months Free is to entice people into subscribing to Apple Music, and the more people that end up scribing the better.

I think at the end of the day (or end of 3 months) more people will have subscribed to Apple Music then before and the artist will be making more money.

Personally i think the real winners are the record labels who seem to get the lions share of the money.

Also when Goole Music was released it was free for a limited time... did they pay artist/record labels?