Originally Posted by
smbk83
As mentioned by others in this thread, there are many factors at play (route type (ie business/leisure heavy), cabin load, etc).
It also depends on your budget and how much you are willing to pay for/value the upgrade (I also take into consideration how much I already paid for the original Y ticket). I always bid as low as possible (just 10-20 EUR or so above minimum bid) and accept Y if I do not get upgraded.
For reference, in May 2023, I flew BER-LIS-SSA. The LIS-SSA segment I got plusgrade bids from Y to C accepted for around 500 EUR. On the return leg, 430 EUR was enough to be upgraded. On both cases the bidding scale of plusgrade would go up to around 1500 EUR.
I also bid as low as possible. I do check my chances looking at actually available seats - if most are sold I can increase it. I’ve been successful with my bids.
The minimum ex-LIS to Brazil with Plusgrade has been indeed around 500 EUR. I’ve never used seatboost though.