Hi DK,
No you are not bonded and yes you do have to pay £21K from your salary (even if you are PPY) however I believe the cost is taken before tax and NI and over a 3 year period. Or you can elect to pay £2400 per month for the first 8 months of service, which comes to £19200.
Once you are in the Company you can bid on to other types and there is no cost or bond associated with a successful bid, although in some circumstances pilots have been frozen on type on joining the Company for 3 years.
The cost of the TR and OCC are not ideal and I believe on the wish list for the union to get rid of.
Regards,
NK