We. Don't. Know.
Look; I'm sorry for being short with you on this, but the glue factory wants that horse, and people won't stop beating it!
And you question is more or less covered under here, an' that topic hasn't even made it off the first page yet...
EDIT; Although I believe it's been said that the moral positions are something like Hero > Rogue > Villain > [i forget] > Hero
Hero/Villains can access only their respective zones + praetoria.
Rogues (falling heroes) have access to blue and red side zones + praetoria. Can only use Wentworths for market purposes.
[I forget] (villains in the process of redeeming themselves) Have access to red and blue side zones + praetoria. Can only use the Black Market for their auctioning needs.
Based on this, I'd assume that in the transitional stage, you can stay with your group, but complete the switch, and you're kicked to the curb. Of course, as far as I know, there's still no beta, and anything can be changed at the whim of the devs. so; we don't know.
"My inner mind has become a reality-cracking overgod. He torments me! Help!"
I don't know.
We don't know.
The people that do know aren't saying anything.
Heck at Herocon, the Devs more or less said they didn't know.
@Catwhoorg "Rule of Three - Finale" Arc# 1984
@Mr Falkland Islands"A Nation Goes Rogue" Arc# 2369 "Toasters and Pop Tarts" Arc#116617
The progression, as we currently know it, is this:
Hero > Vigilante > Villain
Villain > Rogue > Hero
(The switch can be done repeatedly, but it's clear that doing so will be fairly time-intensive and not a simple "click here to switch" process.)
But yes, as has been pointed out, we simply don't know the answer to 99.99999% of peoples' GR questions at this point. Hopefully there will be official info coming from the dev team soon™, but until then, grab a seat and wait here with the rest of us poor lunks. 
Leader of Legion of Valor/Fallen Legion (Victory server)
http://legionofvalor.guildportal.com / http://fallenlegion.guildportal.com
StainedGlassScarlet - L50 Spines/Inv Scrapper | Badges: 1,396
Avatar detail taken from full-size piece by Douglas Shuler here
<QR to OP>
When you find out, lemme know 
We can only theorize.
I think the bases will be like the markets--only accessible once one makes the full switch.
The plastic tips at the end of shoelaces are called aglets. Their true purpose is sinister.
--The Question, JLU
I know it isn't likely this question is gonna be answered just now, but I'll ask anyway.
If I was a blue side vigilante playing red-side with a team of villains, would I get access to leader's VG base?