Ladies and gentlemen, in the US, the major labels sign their new artists/bands on a work-for-hire basis. The copyright to the recording is entirely owned by the label. Some very successful folks may negotiate for their master recordings later in their career.
Or, they can stay independent and develop their career with less capitalization and retain more ownership of their works.
Apple, and all other streaming services, have to negotiate the rights with the recording's owner for streaming. (There's a loophole about pre-1973 recordings. I would guess that major labels insist on getting revenues for those recordings as part of the deal to get post-1973 recordings.)
So, no, no one has to go for three months free. But, no, it's not the band who, generally, has a say.
As a comment on reporting about Apple's WWDC music announcements, currently, with streaming, the people who do the best are the streamers and the record companies with deep catalogs. Apple is a retailer. They, the artists, independents, and the major labels—to the degree they want to develop new artists—want sales, not streams. But sales derive from listens for all but the top tier of musicians. A streamer who also sells should want to create new high value fans and should emphasize discovery and new artists.
Meanwhile, as a consequence of supply, demand, and that nothing need go out of print, listeners know that there's plenty of ubiquitous music available at no or minimal cost, and so the need to buy a track for playing at one's convenience is minimal. It takes new generations, new sounds, and new artists to reinvigorate music. At one time, it also took djs. Novelty is the only scarcity that remains for the music business. Apple is trying to set up their human-curated streaming and internet radio station to maximize, as much as possible, creating new fans and sales.
Here's the thing, Apple has to take a passenger seat because if it gets too aggressive in making music healthy, say, by promoting and signing artists on more favorable terms than the big label recording contracts, the labels pull their music out of the store and streams. And it's an open debate as to whether new generations bond as much with music as compared to the generations of the 19th and 20th centuries.