Can a sponsored worker work overseas during a visa extension?
A sponsored worker whose Skilled Worker visa is being extended must generally remain in the UK while their application is pending. Section 3C leave, which continues their right to work while a valid in-time application is under consideration, ends at the point they leave the UK.
Short trips may be possible in some circumstances but you should contact Borderless before any overseas travel is booked during a pending application. Incorrect travel can void the application.
The 28-day delayed start rule
When a CoS is assigned, the worker's employment must generally start within 28 days of the later of the CoS start date, the visa grant date, or the worker's arrival in the UK. If the worker does not start work within 28 days, the sponsor must report this as a change of circumstance and may need to withdraw the CoS.
A delayed start of more than 28 days for a genuine, documented reason (for example a serious medical issue or flight disruption) can sometimes be accepted, but you should notify Borderless and the Home Office at the earliest opportunity.
Working remotely from overseas
Sponsored workers cannot routinely carry out their sponsored duties from outside the UK. Occasional short overseas work trips as part of their UK-based role are usually acceptable. Extended overseas working is not compatible with Skilled Worker sponsorship and may require a change to the worker's immigration status.
Government guidance: https://www.gov.uk/guidance/sponsor-a-skilled-worker#worker-circumstances