Cee Jay
Striker
Earlier start might mean you miss the worse of the trip buses etc that descend ( pun intended) on the place. The time I went up "the fastest" was caught repeatedly by coaches at hairpins and had to unclip a fair few times.It's either up and out at 7am or options to shave 30km off the ride...don't fancy riding when it's above 25c either...not climbing anyway.
A decent alternative might be to miss Sa Calobra but do a loop involving going up or down Femenia and battala ( the opposite)
Up battala and drop down Femenia or up Femenia and down Battala( I'd go for the former) as going down Battala's switchbacks can be very busy( slow) with coaches, whereas Femenia quieter and is fast and fantastic to ride down and takes you to Pollenca on the flat and new tarmac