Not necessarily this could be due to the better light levels we have had this year.
How far apart are the pairs of leaves up the stem?
Usually when the gap is quite large this can mean that the plants have elongated due to stretching for available light, whereas the reverse is usually true with plants that have been growing in good light levels.
Either way the plant/s will usually flower after the third pair of leaves, so in good condition 12" is OK. In poor light the plants can be 12-18+" before flowering.
If things continue as the are you might find you get an extra truss this year.