From what I am aware of, the ATP Scheme had you on a reduced payment of 'expenses only' ie flight duty pay etc and no salary at all during your first 6 months with said airline. At jmc (as was) this worked out at about £800 per month. Remember that you are not employed by the airline at that point and will just be finishing line training. If you get taken on by the airline you then get the full wage payable to any other F/O or S/O. Many airlines have the S/O rank for just this sort of scenario, ie you have a frozen ATPL. Promotion to F/O level usually comes with unfreezing the ATPL and something like 500hrs jet as a minimum.
What you have to remember is that even though the pay is not so great to start with you guarantee to be on a higher wage than an FI and probably not far off the upper end of a Turbo-prop F/O salary once your 6 months is up. In my opinion you are saving somewhere in the region of 5 years on the average airline career by getting in on a scheme like this as the alternative is to do something like an FI rating after say 6 months of applying and getting nowhere, approx 2 years as an FI building hours, then say a turbo-prop F/O job for a couple of years before applying and getting accepted into a jet operator. (Obviously this is hypothetical and will vary with the market and on an individual basis.) Looked at that way the 'cadet' has earned considerably more in that same time period (probably a full blown F/O after about 2 years starting on approx £37k) with increments in salary each year after, has not had to worry about the 'age vs experience' selection criteria due to being on a 'big jet' all that time and most importantly is now nearly five years into a seniority list (easy excepted of course) which means a number of things;
1. Much safer when the downturn comes and 'last in first out' redundancy becomes an issue.
2. Closer to a command opportunity.
3. Getting a better choice of flying opportunities, basing etc etc if they are chosen on a seniority basis.
If pension is an issue, they have also been 'in' their scheme for longer. Again, not as much an issue these days as very few have final salary schemes, but still a consideration.
So, I'm not trying to flog these schemes, but just point out the benefit of the ATP scheme in particular.
Bonding is another issue and as far as I am aware the airline pay a premium to CTC for the product and will then require you to sign a bond, just like if they had taken you on and paid for your training in the first place.
Hope that helps.
PP