Cathay Pacific Asia Miles - How much danger of new business class on flights to/from Tokyo?

How much danger is there of us getting a plane with new business class on the following flights to/from Tokyo?
In particular, CX548, which is currently listed as a 333 for our departure date (and a 330 on other days of the week)? And CX450, which is currently listed as a 744 for our departure date (but 74J or EQV/variable on other dates)?
Returning, we're concerned about CX549, which is currently listed as a 330 for our departure date (and a 333 on other days of the week)? And CX505, which is currently listed as 744 for our departure date (but 74J for other days of the week)?
Apologies for not being clear about the terminology. I know 74J has the new business class, but am less clear about the other planes (and couldn't find a master list using the search function)? Also concerned about how common equipment substitutions are on this route?
There's amazingly good upgrade availability on all these flights but since we're travelling with our three year old daughter new business class (where we wouldn't be able to see her) is a non-starter as far as we're concerned, and we'd rather go economy if there is any real danger of new business class on these flights?
Any help gratefully appreciated and apologies if this has been asked before

I think 74J is old J class, not new J class?

Highly unlikely that if your flight is a A330/333 that it will be new J class. If it's a 747, it's hard to say since they seem to be juggling 747s at the moment.

I think 74J is old J class, not new J class?

Sorry, my mistake, I stand corrected. Many thanks for your advice.