if your gravity is high and have reason to believe it will drop down then the previous posters are definitely right about kegging as your safest bet. on the other hand, if you bottle with champagne bottles you won't have bottle bombs (imo). this probably means cork & caging which is easy if you have wine bottling equipment around. if you really are moving out of the country then you had better start saving thick belgian style bottles now since you'll never be able to wait the full 2-3 years you're otherwise facing for a fully mature sour.
to answer the thread question of "Earliest I can bottle a sour?", i bottled a sour mashed berliner weisse w/ roselare yeast cake after only 1 week @ 1.011 and had 0 incidents using only 12 oz bottles. some bottles made it as long as 6 months and no bottle bombs!
set I: Pale (3) -> Mild (4-5) -> amber / Victory (20-25) -> special roast (40-50) -> brown (70)
set II: pilsner (2) -> Vienna (3-4) -> Munich (8-10) -> dark Munich (20) -> aromatic / melanoiden (25-30)
encore: smoked (5)