Using the rule of thumb that I've always used, the resin should give you about 1,500 litres. However, I'm not sure if that's meant to be 1,500 litres at 000 or 1,500 litres until it returns to tap TDS (meaning that it would be above zero for some time before.
The formula I use is 500,000/tap tds = litres of pure water per bag of resin. I got my 1,527 litres by multiplying the result by 11 and dividing by 25