According to the preceding table, 11.95V should be used as the final voltage for 50% DOD. The remaining capacity (SOC), even at low current or no discharge, is still at least 25%, therefore the battery won’t suffer any harm. But it is NOT advised to set the final voltage to 11.35V for 80% DOD. The residual energy is already zero percent in the case of very low discharge current or an open circuit. It will seriously harm the battery.
The battery needs to be protected more in this situation. Therefore, advising to set the end voltage to 11.90V or 11.80V according to chart above. 10% to 20% of the original capacity will still be available.
It is more crucial to adjust the battery system depending on the amount of energy utilized per day or cycle rather than just voltage. The end voltage will appear to prevent damage to the AGM battery when the energy usage sporadically surpasses the safety level.