I need to do  job where I will be moving along a shoreline. Has anyone learned a way to change the HOME POINT while in flight ?

Only a few people have the ancient knowledge required for that.
They all started here:

You have two options.
To reset home to the current location of your Phantom
To reset home to your current location (as long as you have a GPS enabled phone or tablet)

Probably either would work for what you are planning.

Question: so if you arent able to set a home point from take off and you fly around an open field, the voice prompt says home point saved when it is 50 yards in front of you, are you able to change the home point at that time to where you acually are? not sure if this is what reset home point means here

fansd393882c Posted at 2-11 11:45
Question: so if you arent able to set a home point from take off and you fly around an open field, the voice prompt says home point saved when it is 50 yards in front of you, are you able to change the home point at that time to where you acually are? not sure if this is what reset home point means here

You do not normally have to set the home point when you start up and fly, it is done automatically. If you get the voice prompt, as you described, then it is likely that either you took off too soon before the aircraft could automatically set its home point, or you took off from a location in an urban or forested area where the GPS reception was weak. In any event, the easiest way to set the home point is to fly back and hover over the desired landing point, then, in the menu described and shown above, press the icon (left one in illustration) to set the home point to where the aircraft is currently. As Labroides says, you can also set it to the location of you and the controller, but you must have a phone/tablet with a good GPS receiver to do that.

Geebax Posted at 2-11 13:38
You do not normally have to set the home point when you start up and fly, it is done automatically. If you get the voice prompt, as you described, then it is likely that either you took off too soon before the aircraft could automatically set its home point, or you took off from a location in an urban or forested area where the GPS reception was weak. In any event, the easiest way to set the home point is to fly back and hover over the desired landing point, then, in the menu described and shown above, press the icon (left one in illustration) to set the home point to where the aircraft is currently. As Labroides says, you can also set it to the location of you and the controller, but you must have a phone/tablet with a good GPS receiver to do that.

I'm asking this because in the summer I went to fly my Phantom over a lake, I started from the pier, it didn't save home point until I took off and moved about 5 feet over the water, the controller started to be and I lost all control of the craft controls. I panicked and hit return home, it went up like it was supposed to and came to me almost straight down 5 feet in front of me landing in the water. I canceled toe RTH went out in the water and had to catch it in my hand, was there anything I could have down to bring it to me with out going in the water?

fansd393882c Posted at 2-11 14:15
I'm asking this because in the summer I went to fly my Phantom over a lake, I started from the pier, it didn't save home point until I took off and moved about 5 feet over the water, the controller started to be and I lost all control of the craft controls. I panicked and hit return home, it went up like it was supposed to and came to me almost straight down 5 feet in front of me landing in the water. I canceled toe RTH went out in the water and had to catch it in my hand, was there anything I could have down to bring it to me with out going in the water?

I suggest it did not save the home point because you took off too soon, and it had not had a chance to get a home point GPS fix. But in any event, if you hit Return To Home while the aircraft is less than 20 Metres away from you, it will not come home but simply land exactly where it is at the time. All this is explained in the aircraft manual, the one you download, not the quick-start one that comes with the aircraft.

If I may add a couple comments...

It's a good idea to get into the habit of making sure you have a home point before you launch.  That means you might have to stand there and wait a minute or two while the AC is sitting in front of you seemingly doing nothing.  

If after a minute or two you still don't have a home point which means it doesn't have adequate satellites, I think it's a good idea to first assess the wind and ask yourself if you're prepared to launch in ATTI?  If the wind is calm enough and you think you can fly in ATTI in the environment you're in, then launch and just rise straight up slowly if you can.  As you gain height, your satellite antenna will gain more and more view of the sky and you will get a home point automatically set pretty close to where you launched it.  

Remember - setting the home point manually won't work if you don't have adequate satellites.  And it's rarely a good idea to fly without a home point.  As Geebax emphasizes, read the manual.  Learn how to cancel RTH quickly and confidently.  

Mark The Droner Posted at 2-11 15:13
If I may add a couple comments...

It's a good idea to get into the habit of making sure you have a home point before you launch.  That means you might have to stand there and wait a minute or two while the AC is sitting in front of you seemingly doing nothing.  

I appreciate the reply's, after the ordeal I had with the remote not communicating with the drone that day I wont be flying ever again without setting the home before take off. that was a bad gut feeling seeing it try to land in the water, thanks for the help

fansd393882c Posted at 2-12 11:02
I appreciate the reply's, after the ordeal I had with the remote not communicating with the drone that day I wont be flying ever again without setting the home before take off. that was a bad gut feeling seeing it try to land in the water, thanks for the help

I think you may have missed the point, it would have landed in the water anyway. Pressing RTH when the aircraft is 20 Metres away or closer causes it to land straight down, it will not fly back to the home point first.

Geebax Posted at 2-12 14:32
I think you may have missed the point, it would have landed in the water anyway. Pressing RTH when the aircraft is 20 Metres away or closer causes it to land straight down, it will not fly back to the home point first.

oh no I didn't miss the point I knew that because it happened to me, I had to get in the water to catch it