Good filmmaking can get around that. Look at RED OCTOBER. You're at the end of Act 2 and the subs are kind of 'talking' ... and then you have a title on screen saying something like '20 hours later, the laurentian abyss' and you go right on with things.
If you did that wrong, it would be a dead stop for the movie, but they handled it properly. Then again, that was McTiernan on a very good stretch of days (which he has not enjoyed thus far this century.)