Does anyone know what the Altitude Optimization feature does in the gs rtk app? Should I have it on when flying my 2D ortho missions ? Does it correct the Altitude at the end of a mission for all photo captured during flight? Would one load those extra photos into the Drone Deploy software when making my ortho maps? Thanks

Altitude optimization adds a survey line from the outer edge of your mapping area in towards the center along which oblique (45°) images are captured. This is intended to improve the vertical accuracy of your point cloud and DSM, which will suffer from increasing error correlated with flight altitude without the obliques (see Accuracy and Precision of P4P RTK thread).
You should enable this option if you care about the vertical accuracy of your photogrammetry products. I don't know how DD makes use of them but Pix4D definiotely does.

Thank You for your knowledge on that. I also have a quick question on the DRTK2 base station. Is it true that if you are using the base station as a stand alone station, no benchmark or known points, just set up in an open field,  there is no need to add or subtract the antenna height in the Z value because the software already takes this into account for the value of Z displayed? So just connect to P4rtk  and fly mission? Seem like a lot of videos I watch on the setup of this, there is never a mention of going to adjust the Z value for antenna height.   

If you're not entering coordinates into the D-RTK 2 and just using its (imprecise) solution instead, you don't need to worry about antenna offset as the solution is for the Antenna Phase Center. If you enter the coordinates of a benchmark over which the D-RTK 2 is set up, you need to account for the height of the antenna over that point when entering the Z coordinate.

Thank You !!!