Before choosing a project, because the funding record often sets the real timetable. Retrieving archived statements, obtaining accountants' confirmations and translating foreign documents can take months, and one missing link can hold the whole petition. Starting early also reveals whether the intended sources can be evidenced at all.
Work backwards from the transfer date
Fix a target date for placing the capital, then schedule the retrieval, translation and review steps behind it, giving the slowest foreign records the most room. Keep a list of outstanding items with an owner and a due date for each. After filing, the pace belongs to the government and to visa availability, so no completion date can be promised.
Revisit the plan whenever a source changes or a record proves unobtainable. Add one instruction to that schedule: request the oldest records first, on the day the plan is agreed. Archived bank statements, closed-account histories, and documents held by institutions that have since merged are the items most likely to take months or to prove unavailable, and they are also the ones people postpone because the request feels premature.
Everything else can be produced faster than it can. Hypothetical example: an investor sends four archive requests in the first week — two to banks, one to a former employer's payroll provider, one to a property lawyer — and by the time the narrative is drafted three have arrived and the fourth has been replaced by an alternative that would not have been found in time otherwise.