The new application went live on July 1. The updates to the website (where you can search through current openings accepting applications) went live July 15. They are transitioning from the old process to the new one. If you've applied for a program departing next April, May, or June, you'll know whether or not you have an invitation by January 15 (if not sooner). You generally can't apply more than 12 months in advance for a program, as they don't know what the volunteer requests are until approximately 12 months in advance of the staging.
In the new process, there are no more pre-clearances. All medical tasks and submitting your fingerprints for the legal background check will be done after invitation. But that does mean people will have to be on top of getting their stuff completed and submitted as failure to do so will prevent you from departing.
If you're still hoping for a January/February/March assignment, the 4 month minimum rule is still in effect. In other words, January programs will receive invites no later than some time in September, February in October, and March in November.
I think the ideal of the new process is that people will largely wait only 6 months to know if they're invited or not. It could still reasonably be a year from the day you apply to the day you depart. I think it will still be a good practice to apply earlier rather than later.