Independent evidence-gathering can begin immediately; a colleague's statement can support the file but should not be the only step being taken while the timeline runs.
Start primary documentation without waiting on one source
Begin collecting training and project records directly from company files while any supporting statement from a colleague is being prepared, so the timeline is not dependent on a single person's availability.
Gathering and organizing internal procedure documentation typically takes longer than a straightforward petition, so preparation should begin well ahead of any planned transfer date. Keep the proposed start subject to the appropriate immigration steps and the actual revised evidence. The expense is a second evidence assembly under deadline, the internal hours it consumes, and the delay to a start date that the business has already planned around. Have material changes reviewed before relying on the original support narrative or proposed start date. Gathering internal evidence and obtaining a considered supervisor comparison can take substantial time, and a request for additional evidence would extend the timeline further. If the revised job is ordinary technical support using general industry skills, the original approval theory may no longer fit; preserving it unchanged is the common mistake.