@Sysm has completed 50% of the service, but not all experience was valued at the same rate.
30 to 60 Woodcutting is 257,379 XP. The payment for this service was decided to be 3M according to the skype logs. Making it 11.655 gp/xp
47 to 60 Woodcutting is 198,615 missing XP. This would mean 2,314,857 gp is to refunded for the woodcutting service.
40-70 Attack is 724,264 XP
65-70 Strength is 288,199 XP
60-70 Defence is 463,885 XP
The total sum of this xp is 1,476,348.
67-70 is 189,674 missing XP
66-70 is 241,373 missing XP
60-70 is 463,885 missing XP
The total sum of this xp is 894,932
The payout was 14M. Equaling 9.482gp per xp. Meaning that 8,485,745 gp is to be refunded.
A bond is the purest base for membership so I will be using this for the formula to gp.
A bond currently sits at 2,625,372 according to OSBuddy. When one exchanges a bond for membership they receive 14 days of membership equaling to 187,526 per day. Meaning that 375,052 worth of gp was 'wasted'.
Summary.
2,314,857 gp for woodcutting.
8,485,745 gp for combat
375,052 gp for bond.
11,175,654 gp in total should be refunded of the 17M.
The 2m in supplies should remain in the account.
As a precautionary measure, I've placed @Sysm under twc and asked him to post here, he has 24 hours to do so.