I think Cutler says to go to around 200mg doses of ala for a while when you no longer feel side effects. He says tests will normalize long before that.
I had a nasty lead problem. That comes out of bone very slowly. Since my health was back in the normal range for my age after 1.75 yrs of detox I stopped chelating every weekend. I do a round when it is convenients but at least one per month. AC says that's enough to remove lead coming out of bone after the first year or so.
there are so many factors:
how do you tolerate the doses
do you have $ for optimal supporting set of supplements and maybe meds
can you do long rounds or have to stick to 3- day due to work or family obligations
age--younger folks tend to heal more quickly
other medical problems that cause additional problems
can you afford or legally obtain DMPS or DMSA along with ALA. They help to move things along.