Mercury reaches 4 degrees of Aries where it will stay until it moves forward. It turns direct April 15, at 5:21 AM, EST, at the same degree. It actually turns stationary retrograde at this time, and does not move forward until April 17.
During the stationary direct period (April 15-17) things may become more confused or change direction once again before they get better. It's best not to rush out and start new things as soon as Mercury turns direct. Rather wait, and let the dust settle a little if possible.
The post retrograde shadow period lasts until May 3, then things are at normal pace.
I personally thought this was a rough retrograde and we also had to deal with Mars-Saturn, which proved a difficult and frustrating time for many, along with Mercury square Saturn, which interferes with communication, slows things down, and is generally tiring all the way around. This will repeat itself April 24-25. Mars in Capricorn will conjunct Pluto over the next several weeks, and this will be quite intense before the month is over.
But, at least Mercury will straighten up and fly right and we won't have this pesky trickster threatening to screw things up at the last minute every time. With Mercury retrograde in Mars sign, communication has been intense if not angry and frustrated. This should change for the better as well.