How to Change Start Date for Move to HR Phase

Summary:

How to Change Start Date for Move to HR Phase and re-issue/redraft the offer letter

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As in most of the countries candidates are moved to HR soon after offer accepted.

But then say in H1B transfer cases , it is quite common scenario until the visa is transferred he cannot be hired, which ultimately pushes his start date,

How do we handle such a situation to ensure latest start date mentioned offr letter is issued to candidate.

We are very curious to know how other countires are handling such cases as it is pretty common hiring process.