Fix the region and the base first, because both determine what evidence is needed. Then collect site confirmations, which run at the slowest site's pace. The duty statement and worksite plan come last, once the boundary and the locations are actually settled.
Expect the slowest site to set the date
Confirmations from several leaders will not arrive together, and a site in the middle of a budget cycle or a leadership change may take much longer than the rest. Start every request in parallel on the first day. Where the region is due to be redrawn, decide whether to document the current structure or wait.
Agree the base before travel plans are made, and keep the start date behind the last outstanding confirmation. Send every site request in parallel on the first day, because confirmations will not arrive together and a site in the middle of a budget cycle or a leadership change can take far longer than the rest. Fix the region and the base first, since both determine what evidence is needed, then collect the confirmations, then write the duty statement and worksite plan once the boundary is genuinely settled.
Where the region is due to be redrawn, decide deliberately whether to document the current structure or wait for the new one. Agree the base before travel plans are made, and keep any start date behind the last outstanding confirmation rather than ahead of it.