Question about changing the trany fluid and filter

Just changed the fluid and filter in the 92 735i (4HP22) and added the suggested 3litres of fluid (according to the Bentley manual). Then I checked it and the dip stick was not wet except for the balls (from the fluid on the sides of the tube). I added another 250ml and same thing. I added ANOTHER 250ml and same thing again. Car was warm (170 degrees), in Park and running. I drove it around the shop and checked it, again same thing. When I dropped the pan, it sat for a couple of hours. Could it have drained more that way. Also the car was tilted with the rear lower than the front. Might that have drained what was in the line to the rad.

My question: do I keep adding? It’s the winter car so it’s still in the shop and not being driven right now.

Thanx

Question about changing the trany fluid and filter