The Home Office strongly recommends against making travel arrangements to the UK before the visa has been issued.
Travelling to the UK as a Visitor
Once an online application for Global Talent visa application has been submitted, or once the Global Talent visa has been granted, the applicant must not enter the UK as a Visitor (for example, as a tourist). Doing so will invalidate the Global Talent visa, and they will not be able to start their employment or engagement.
Travel arrangements should be made to arrive to the UK on or after the Global Talent visa issue date.
Any concerns around travel plans should be discussed with the employing department/ faculty/ college and the Staff Immigration Team (SIT).