I think you will find there is a big difference for the cadets in the first 4 years. Most importantly, after 4 years the KA cadet will be a Senior FO with the appropriate pay for the rank and will have accumulated enough P1 hours for his ATPL. The CX cadet with 4-5 years of SO on the jump seat will be playing catch up for a long time - he will need to do the appropriate number of P1 hours after his SO time before his ATPL can be validated and it will be a further number of years before his basic salary matches the KA cadet's.
Therefore, time scales not the same and remuneration definitely not the same.