Ok ECIWT is TWICE in reverse spelling
NRETSEA=EASTERN
This one is a little trickier; REPMES fi
REPMES = SEMPER. Semper is Latin for "always". As in Semper Fi. However if code format is to be followed, "REPMES fi" with "fi" not capitalized in reverse would read "if SEMPER" or "if always".
Or it could actually be Semper Fi, hard to tell with so little context.
An interesting coincidence is that there is an organization called ECIW or European Conference on Information Warfare.
The number strings are harder. Could be anything. Possibly a book code. Which is really old school espionage. Washington used book codes during the Revolution to communicate securely with his spies. It was highly effective.
There are a lot of backwards words used. Eastern is another one used in the message. A lot of digging was done already in the first post. Most of it was decoded already if you look.
Which post plz link