L/H/E Fuse changing

hello, I have a question on subject:

Can someone change the L/H/E Fuse settings without altering the content of the flash?

Or, in other words, if a nano has a sketch uploaded, can some change the fuse settings and the program to be operational after that?
thank u

Yes, just don't do a chip erase cycle.

ok this and thank you.

I believe that lockbits are handled differently i.e.

if chip is unlocked, it can be locked without erasing the program, but if the chip is locked, unlocking cannot be done without erasing program.

Correct?

demkat1:
ok this and thank you.

I believe that lockbits are handled differently i.e.

if chip is unlocked, it can be locked without erasing the program, but if the chip is locked, unlocking cannot be done without erasing program.

Correct?

Yup

have a nice day