definitely a case-by-case as well ... but i was staying in a new marriott hotel and i could show a long term duration (12 weeks) and i convinced the manager to upgrade my 'hilton' colleagues to marriott platinum if i got them all to stay with me at the marriott.

she obliged and now they have marriott status.

So if you can also get a 'status' friend or fellow traveler to vouch for you ... that never hurts!

good luck.