Depending on the type of battery 12.4 is between 50% & 75% SOC so too low and would indicate a bad battery if you have had it on charge.
You should put your meter on the battery then turn the ignition on and read the meter.
There is a very good chance your headlights are pulling your battery down to a point where it can't illuminate your dash lights.
When that happens the chances of the 30a fuse failing greatly increases.
Some of the 19 rides in my shed
2014 V2, Snoopy
2009 Wee, Pumbaa the pig
WR450F, The Blue Postie Bike
YZ250N smoker with rego, Stinky.
Yamaha MT09 (FZ09), The Scud missile.
Club Lead not Club Med.
He with the most toys wins.
Out of my depth in a puddle.
Live life on the edge you will see more that way.
Ridding a motorcycle keeps things in balance.
At the end of each trail and at the end of each day history is made.