[Samba] NT4 & Exchange 5.5 running with Samba 4.5 AD

[Sonic]

File under blast from the past...

Any known reason that an NT4 domain member of a Samba 3 PDC running
Exchange 5.5 would have issues if the PDC is migrated to a 4.5 AD?

I know that early MS AD's supported NT4 and Exchange 5.5. but I'm not
sure about current Samba AD releases. The only caveat I can think of
is that apparently (not 100% sure of this) the nmbd process that runs
in AD mode doesn't support WINS or NetBIOS browsing in the way
necessary for the older combination. But that can be worked around by
using a Samba 4x file server as an AD member and have it run nmbd with
WINS support.

Any input is appreciated.

Thanks!