yeah. Switching from Run to Remote is easy. It will allow you do perform online edits. Be careful not to accidentally switch the key to program mode... that tends to cause issues hahaha...
One thing to keep in mind... if they've added an eeprom, it may be set to auto-load the progam when power is cycled. If that's the case, you'll need to find a time to flash it, and/or be prepared to possibly lose the edits the next time your plant has a brownout