Just had kind of an annoying experience with GS.
12 days ago I booked IAH-FRA-(LH)-DEL-ORD-CLE in J for Oct 7-14. Used PPs to waitlist FRA-DEL on LH to F. 40 PPs deducted.
Today I had to switch the return to BOM, so basically just added a Vistara leg from BOM to DEL but otherwise prior segments remained intact. Nevertheless, got one of the dreaded "your ticket must be reissued" notices. So I call GS.
Agent says "Well first let's clear out the [LH] waitlist, because you've cleared." Wow, I thought, this is great! But the cynic in me was also suspicious that this must be too good to be true. After a few minutes while still waiting on agent to confirm I had already paid the $3 fare differential, I checked the LH app and noticed that I was still booked in J and that the F waitlist had vanished. I then told the GS agent that it looked like she had cleared out my LH F waitlist. She said "Oh, I'm sorry, I thought you had waitlisted for J and that it had already cleared, isn't O business class on Lufthansa?" I said "No, I think that's a fare code for F. I guess I will have to go back and re-apply the PPs. Will I get the prior PPs back?" To which she said "They don't deduct them until they clear." Here again my inner cynic seemed to think that this was not the case for LH, but I let it go, hung up, then re-applied the PPs.
I'm back on the waitlist, except now I have 80 PPs deducted instead of 40 (put differently, it seems I've had 40 PPs deducted on two different occasions for the same flight). At this point I do not want to call back and try to get 40 PPs immediately credited because I don't want to mess up the reservation any further. Maybe it will fix itself.
I guess what I have lost at this point is the extra 12 days of upgrade priority (if LH uses that as a tie-breaker), and the risk that if it clears I may lose 80 PPs instead of 40 (but would rather battle later to get those back in the happy event of an upgrade).
This agent seemed otherwise competent and knowledgeable, but she whiffed on this one and I should have gone with my instincts and intervened sooner.