Hello Boba,
It’s normal for both ALT and Viral load to fluctuate during the acute phase. It looks roughly like this:

About 25% of patients clear the virus and you can see the comparison here where one patient clears the virus and the other patient does not:

Dual genotypes probably occur ~ 10% of the time but are less often reported. Over time, whatever genotype reproduces fastest will become the dominant one, so in your case, it looks like the GT2 more or less beat the GT1a in the cloning stakes.
Epclusa works on both GT1a and GT2 (and all the other genotypes) so your cure rate is not better/worse because of this.
Early treatment tends to be more effective than later treatment as there has not been time for cirrhosis to develop and we know this makes treatment harder. It’s probably only a 2% chance (1 in 50) that you won’t clear on 12 weeks of Epclusa. While it’s nice to see undetected on treatment if your ALT/AST are good, then things are going well. Once you finish the pills they wash out in a week, giving the virus 11 weeks to grow back (if still present) which is why we wait until SVR12 – 12 weeks after the pills finish – to declare cure (it’s 99.7% certain you will remain negative indefinitely if negative at SVR12).