I've got no knowledge of that exact program, but here are my thoughts, in general terms, on what you've described.
There is currently a big instructor shortage in most parts of the world. There are several schools out there which, if you turn up at the door with a FI rating, will ask you when you can start.
What you describe basically comes under the category of "working for free".
I reckon that you ought to get at least £12/hour as a flying instructor, probably more than that. So, if you're talking about building 1000 hours, then they "owe" you £12,000.
So, if the price of the course is £12,000 less than you could get the same set of courses elsewhere (including FIC), go for it. If it's not, do the same courses somewhere else, including the FIC, then find work as an instructor. You'll get the same 1000 hours, but be less out of pocket because of the salary you'd earn as an instructor.
FFF
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