It is high time [we went home].
It was time [somebody did something].
It's time [she didn't confuse our names].
I don't know why you mentioned the 'subjunctive mood'. Even if English had one (which it doesn't), the bracketed elements would still not be subjunctive clauses.
They are in fact declarative content clauses functioning as complement of "time".
Note: for more advanced learners, these are extraposition constructions where the subordinate clauses are best analysed as being in post-verbal position, serving simply as a semantic argument of the verb phrase.