Ultimately only you can be the decision maker on this, but a few helpful pointers:
1) What is your normal flying schedule like - if it something like 2 or 3 long-haul trips a year then you have to evaluate how beneficial incurring a large cost to reach GGL is?
2) If the above still holds true, but you fly every week for work around Europe then the use of the CCR at T5 and priority when the sh*t hits the fan during IRROPS does prove to be worth it
3) 1500 TP’s is a lot to try and earn between now and the end of the year - have you priced up how you could earn that because at this late stage I would think several thousand pounds would have to be paid out to earn that now.
4) Going for it next year at the normal levels again brings us back to the above questions and earning 5K a year to hit the initial threshold is not easy - that is a high number for a reason!
Pilot37