Complex sentence: Walliams confirmed on 16 January that the first golden buzzer was used by Holden at the Liverpool auditions, whilst Dixon and Ant & Dec both pressed theirs on 23 January, whilst Walliams himself pressed his buzzer on 27 January at the London auditions.
Split into simpler sentences: Walliams confirmed on 16 January that the first golden buzzer was used by Holden at the Liverpool auditions. Walliams pressed his buzzer on 27 January at the London auditions.