Ordered July 24th (white, vanilla SR+), switched to leaseplan on the 14th of August - just ported my RN so shouldn't have effected my order. Still waiting. Guy who used my referral code got his before me *shake fist*
Mine was a white/black Performance so not the same but I took delivery (which I delayed by a day) 7 weeks and 2 days from ordering and I wasn't a reservation holder. Personally I think that they will have got through most of the backlog now other than the 'unicorns' so I don't think you will wait any longer than that personally.
Its not an easy question. Since they started releasing inventory some have waited as few as 3 days to get their car. Early orders are probably the worst possible example as there would have been a large amount of initial demand that has taken time to fulfill so what the lead time for delviery is going forward now the dust is settling is still unknown.
Personally I'd wait and buy inventory when it appears being a litle flexible on spec (not that there is any at the moment) , but you can sign up to the mailing list on the 3rd party inventory sites. Its actually quite difficult to manage an exact delviery date with Tesla.