Any published processing arrangements are stated on the official page. The household's own timetable is usually set by liquidity and by how long its immigration history takes to document.
The domestic clock is the slower one
Read the official program page for the process and for any timelines it states, and record the date you read it, because the material has been revised before. The slower clock is usually domestic. Exercising options, selling shares within permitted windows and settling the tax on those transactions takes planning and often spans a tax year, and money that is expected is not money that is available. Documenting an earlier refusal or an old admission can also take weeks if files have to be requested from an authority. A sensible order is to confirm the current official terms, then eligibility and admissibility, then liquidity, and only then to act. Paying a non-refundable fee before the first three questions are answered guarantees a loss if the answer turns out to be no.
Order the slowest civil documents first, since they depend on nobody's decision; leave the medical to the timing the instructions specify, because validity periods can lapse; hold irreversible household decisions until a visa is actually issued.