Why have many TV shows aired 11 (of 22) episodes before Christmas this year?

Just noticed that many TV show this season have aired 11 or more
episode so far this year. For example CBS's "Close To Home" has aired
11 episodes this season so far. Last season it had aired 10 episodes
before Christmas. Other shows displaying this "more episodes before
Chrstmas" phenomena are "ER" and "Bones", I also noticed that if a
show is likely to get a 24 episode season it tends to air 11 episodes
before Christmas too.

While other networks like "the CW" air about 9 episodes before
Christmas.

Why have many TV shows aired 11 (of 22) episodes before Christmas this
year?

SoHillsGuy...

"Jericho" and "Heroes" have each aired an uninterrupted strip of 11
episodes.

William George Ferguson...

The networks are treating more shows to the 'unbroken strips, few or no
repeats' model. With this show, they'll run an unbroken strip in the fall,
ending with a natural break and/or cliff-hanger, then run a few repeats and
a lot of pre-emptions until late January or the start of February, when
they'll run another unbroken strip of new episodes.

The old model was to run 4 or 5 new eps to start the season, put in a
repeat right before November sweeps, run 3 or 4 new eps in November,
possibly run a new ep in December, run a couple of new eps in January, run
4 new eps in February sweeps, run 2 or 3 new eps in March and April, then
run the final 3 or 4 eps in May sweeps.