Can't help with any refund advice, but this changing of pre-selected seats seems to happen all the time, which rather makes a mockery of going through the exercise.
For my medical / toilet issues,we try to select the rearmost row of 2 seats, which because of the shape of the fuselage reduces the rows from 3 seats to 2, and I pick the aisle. Recently I confirmed this when checking in Online 23.59 hrs before a flight alone without Mrs. ExS on that occasion, but couldn't print a boarding pass so had to queue and talk to a human at the airport, when I was given a boarding pass for a seat further forward and in the middle of 3.
Ugly scenes followed, ending with a Supervisor categorically refusing to tell me why the change had been made.
In the gate lounge I again approached an Agent, younger and more helpful, and he eventually giving me my original seat ! He then explained, and I subsequently heard the same supervisor give him a bollocking for explaining to me, that 2 inbound pax. were to be deported (from the USA ) and the Federal Agents had demanded the rearmost middle tier of seats, i.e. 4 seats together for 2 crooks and 2 agents, and they didn't want anyone sat in the adjacent seats across the aisle on either side. I also learned from another source that the airline had been given strict instructions not to advise pax. of this reason for seat re-assignments. ( why ? Presumably they didn't want their charges to be the centre of prurient attention ? )
In the end, the posse didn't board, and the crew offered my window seat companion the whole row of four to sleep on, leaving me where I had originally chosen to sit, and with spare space alongside, i.e. no fight for the armrest !!
2 months later, Mrs. ExS and self experienced another change on arrival at the airport, moving us from the same two of 2 seats to a row of 3, leaving me in the middle, with a fat slob at my side. I won't bore you with that one, suffice to say no extra charge for the seats we had selected, so no contest.
Last edited by ExSp33db1rd; 25th Dec 2017 at 05:52.