Assuming there's no change in the EE (and I don't think there is), you can take as long as you like to go back to Aran.
Good to know; I didn't do any major quest lines beforehand though, besides dealing with Cecile, a moneylender from Questpack. It cost me 6k of my gold to complete the Good way, but I finished it anyways.
Delta, human Kensai/Druid, 4th update
As mentioned, we paid a ransom for a little girl that had been kidnapped by Cecile's thugs. From there, the only new gear we get is several potions of Genius and Mind Focusing, both for memorizing spells and not dying to Mind Flayers, leaving us with 3k gold for other locations, if we survive til there. Jan and Anomen are taken along, basically the only two characters that are easily accessible without starting any new quest line/traveling out of Athkatla.
Vampire Ambush: Anomen gets drained, Aerie almost dies to... something. I think it was due to one of the Vampires changing into Bat form, and for some reason kept dealing damage to anything near it. It wasn't rolling attacks, and it also couldn't be targeted. I lured it out of bat form with a summon, though, and Delta finishes it off with his dagger. It turns out that you can save Sanik in my install; probably also from Questpack? So we save him, kill Chremy for the amulet, and invade the guildhall to save Claire. We decide that the best way to proceed is by killing Perth for his wardstone, but after Tanova I'd rather not try a straight-up fight. Instead...
Delta moves in under II from Jan and assassinates Perth with Harm.
In the Asylum: Delta gives up a point of DEX, since 19 - 18's only difference is 1 THAC0 to range, which I haven't touched much; I'm carrying throwing daggers, but haven't had to use them. The avatar of Bhaal is fought man-on-man+spider and defeated. Delta didn't even lose all his Skins. And tada!
Imoen's back!
In the Spellhold maze: there've been only three sketchy fights. The first was fighting the Pit fiend, who killed Aerie with a Fireball centered on itself. One Raise later, we continue. Second sketchy fight was turning the pages of the book... The Beholder stripped all of Delta's protections, including the important Death Ward. It fell before it got to cast anything else, fortunately. Lastly was one of the two Yuan-ti mages in the upper floors.
AHHHHHHHHH! Delta didn't even have to save, though; the Aerial servant was somehow the only thing affected, which I am totally not complaining about. We had to search every container an additional time to try to find a wooden stake for Dace, and finally consulted an online guide when I couldn't find one; I missed that a kobold had dropped a set. Onto the next floor!
There've been no crazy fights as of yet, though the Yuan-ti mage managed to Dispel basically every active casting we had. When we fought the Noble Djinn, I found to a bit of annoyance that we had no non-magical weapons besides ammunition, so Delta finished it off with throwing knives. We just finished the Clay Golems for the Gesen Bow String and obtained a pair of Boots of Speed. Two Clay Golem curses are upon us right now, so we'll take one more rest before continuing.
Stats: Delta, Human 9/13 Kensai/Druid. 124 HP (11 from Ioun stone). 226 kills. Most Powerful Vanquished: Perth the Adept. Favorite weapon: Trollmelter. Favorite spell: Barkskin
Minsc, Human 11 Ranger. 104 HP (5 from helmet.) 130 kills. Most Powerful Vanquished: Greater Wolfwere. Favorite weapon: Two-handed Sword (Lilarcor.) Favorite spell: Cure Light Wounds
Anomen, Human 12/7 Cleric/Fighter. 102 HP. 19 kills. Most Powerful Vanquished: Ulitharid. Favorite weapon: Flail of Ages +3. Favorite spell: Chaotic Commands
Imoen, Human 11/7 Mage/Thief. 67 HP. 2 kills. Most Powerful Vanquished: Ice Mephit. Favorite weapon: Bow and Arrow. Favorite spell: Stoneskin
Aerie, Elf 9/11 Cleric/Mage. 47 HP. 25 kills. Most Powerful Vanquished: Thief. Favorite weapon: Sling and bullet. Favorite spell: Cure Light Wounds
Jan, Gnome 10/11 Illusionist Thief. 53 HP. 1 kill. Most Powerful Vanquished: Guard. Favorite weapon: Crossbow and bolt. Favorite spell: Stoneskin.
Permanently dead: Jaheira.