I tried this out with 3BTC expecting 3.015 back. So far I've gotten 2 tx back that total 2.9996. Was I charged the miners fee twice or am I just waiting for another tx of .0154?
It can sometimes be a bit delayed, let me know if you still haven't received it in in an hour.
The miners fee depends on how many times the mixer decides to split the transaction. The base fee is 0.0002 BTC because the minimum split is two, if your tx gets split into 4 the miners fee will be 0.0004 etc. It depends not the size and random variables.
Will it ever happen that it switches from bonus mode to charging mode after an address to pay is generated? Or does the right to a bonus stick with any address generated during bonus time?
No the bonus is recorded in the forwarding entry at the time of creation. However if the backlog of paying transactions has cleared by the time your tx gets used then the bonus may not be paid (only the miners fee will be charged).
any chance to be refunded since the fee wasn't advertised?
If you genuinely didn't know about the fee then yes, please PM me an address.
