Machine is shedded year round and I keep up on the maintenance. The parts are impossible to get fast. I had to special order knife guards for the 540 platform... don’t get me wrong I love the machine it’s just the service and parts. Put it this way... took over a month to have them come out and replace a track on my 765.I would say first, talk to your dealer about improvements that can be done to help with your issue.
If there is no improvement with the service, try to do more of the repairs yourself. Pre-season maintenance is critical for a smooth harvest. If parts availability are a problem, consider working with a different dealer that you can build a relationship with. We have Ziegler and they are top notch. I have dealt with Butler and they treated me very well also for a few odd, aftermarket parts. They are all willing to ship and that can be done quickly today.
If that doesn't work for you, time to explore different machines with a dealer you are comfortable with.