No, major modifications will have limitations during the settlement window. They will only be available for stations identified as mutually exclusive (MX) in the public notice announcing the window. Major modifications in this context should solely serve the purpose of resolving mutual exclusivity issues.
Applicants seeking to make major modifications for reasons other than resolving mutual exclusivity will need to wait for another filing window, which may be several years in the future. It's important to note that if you need to make a major modification due to interference concerns, you can request a channel change to any available channel, not restricted to adjacent channels, provided you can demonstrate reduced interference.