The GoPower Manual says that it may operate in Absorption mode for 1 to 2 hours a day at 14.1 to 14.4 volts. It will otherwise operate in Float mode at 13.7 volts.
These voltages are when the solar panel is producing power and the solar regulator is operating to charge the battery, not connected to shore power.
When it is dark and some time has elapsed from significant charge or discharge of the battery, the voltage at 100% state of charge will be about 12.7 volts ("no load" voltage), according to this source:
Battery voltage and state of charge - Energy Matters
If you are seeing 12.7 "no load" volts at night the solar regulator should be showing 100% state of charge and the battery is fully charged. This is good news! It would be normal for the voltage to go down during the night if you are operating lights etc. plus normal slow battery discharge. In the morning when there is light on the solar panel the voltage should go up but it would be a mistake to believe the regulator state of charge estimate since the battery is under charge.
As I said before, when you are not connected to shore power and using your solar system, the only time the GoPower regulator gives a reasonable estimate of state of charge is just before dawn or a few hours after dark, provided there is no significant power consumption.
I don't think you need to worry about equalization right now -- the cycle is meant to run about once a month for a few hours and the solar regulator looks after this.