I'm not a trainer but I can relate to changing coaches and finding they want you to completely change your style.

I have found new coaches generally have something to add but if you have something that works for you already you don't want to loose that either.

I'm not sure how your trainings are structured but in my gym we have a reasonable amount of training time when we work independently doing shadow or bag work without being watched too intensely.

My solution has been to keep practicing my own thing a little to hold onto it but still learn the new stuff.

There are some things I don't like which I might never pick up and use in a competitive fight but if I've tried them at least I know what I do and don't like.

I think most coaches might not expect you to be able to learn absolutely everything they have to teach especially if you come from a different background so if you learn some of it you might still keep your new coach happy.

Of course if you feel he doesn't know his stuff at all you might want to look elsewhere.