If there is no more leak, the rot should stop, is what I've been told. The issue with rot is that it spreads, because the cause of the rot still exists.
That's been my dilemma, too. First off, where did the rot come from? My trailer is dry. But clearly, for a sustained period of time, something got that part of the floor wet. My trailer came from BC, so a much wetter climate. I still don't know how it got so wet.
But feeling the squishy floor, it gets much, much better as I move toward cabinets and dinette, but I have to assume that there is some rot under there, just not nearly as bad. Ideally, you fix it all. But...if my trailer has no
leaks, and the rot is as bad as it'll ever get, then the only reason to fix it is 1- because it bothers me or 2- because an informed buyer, if I ever sell it, will either walk away or low-ball me (rightfully so) because of the rot.
So it's a tough one. I don't like the squish, but in the scheme of things, considering the size of the job, I'm not sure I care enough. Assuming, of course, that the rot is not progressing.
The rot directly in front of my fridge is bad enough that the linoleum is starting to peel. I'll likely do as much as you've done at some point. Not sure if I'll go any further...