Q. I retired from the Transportation Security Administration on Aug. 1 under CSRS Offset. I was employed in the 1970s and 1980s and owe approximately $42,000 if I wish to buy back this time and get credit for it in my annuity. I was considering using my Thrift Savings Plan dollars for part of this buyback instead of taking the TSP as an annuity or lump sum. Is it possible to transfer the TSP balance to CSRS in some way so that I would not pay a withdrawal fee or taxes on it? (I am 66).