12V Battery charger voltage - cycle use
The Cycle Use is the voltage the Battery needs to become completely full, but it should not be held at that voltage, because the cells don't really like that. The Standby Use voltage is the voltage that the battery can be kept at once it is full to keep it in good shape "on the shelve" until you need it.

You can easily charge the battery at 13.5V, but it will not become completely full, or if it does it will take very long. There is nothing really stopping you from that, but you will not get the full range you could or should.

Whether it is compensated by more charge/discharge cycles depends on the Battery Chemistry, but as far as I know the balance is always worse with lower storage. Seeing your voltages I'm guessing Lead-Acid or LiFePO4, in which case I'm fairly sure you'll get more total-life-time-range when charging them according to specification.