Never use Read GPS twice on a project. On the 2nd day setup in Equip / GPS Base use the "From Known" tab and the "Read From File" button
Store a point thats easy to get to on the 1st day after staking out all your known Control Points and checking that you are properly localized. !!! Stakeout this point 2 to 4 times a day and every time you setup your base or start a new CRD coordinate file on the same project
The easiest way to move a base is to store a point with the Rover then use "Previously Surveyed Point" to setup your Base over the new point After starting a Base with Read GPS, Enter Grid, Previously Surveyed Point or Use Local Coordinates we recommend saving a *.REF file then revert back the next time we setup to using the "From Known" tab and use "Read from File".
You can click the link below for the method to setup a GPS Base over an unknown point and record static data to submit to OPUS: Opus_Base Setup_Rev2.pdf
You can click the link below for some further Documentation on using GPS equipment: GPS Base and Rover Guide