Does Beagle use the reference genome for both phasing AND imputing genotypes?

Question

[giulia.trauzzi]

Hi, I am phasing/imputing my genotypes and I am using Beagle. I am providing a reference genome for the imputation and I am not 100% confident that Beagle uses the reference panel (ref) for both phasing the genotypes and imputing them. I know it uses the ref for imputation but I was wondering if it also uses the same reference for phasing.

Anyone can confirm?

Thanks!