Passenger Trains > Stacked up in Richmond (Staples Mill)

I was listening to the Richmond area feed for a little while before supper. I heard the crew on CAROLINIAN #80 tell the DS that they were going to pick up three locomotives on TK 5. The traihn arrived at 4:09 pm but did not depart until 7:33 pm. Meanwhile #90 ran past the station on TK 2 and reversed into the station on TK 3 after a southbound freight cleared. Amtrak #195, #91 and #53 were all lined up on TK 3 waiting their turn to get into Staples Mill. It appears that #157 and #99 were also delayed - possibly by this congestion.
#80 was over two hrs late coming into RVR, so he may have had locomotive problems and run in with a borrowed unit and picked up the others so that there would be a cab signalled leader over the RF&P.

Andy

Amtrak showing the train at Fredericksburg 8:30 pm
ETA NYP 12:44 am, 3 hrs. 55 mins. late

Cingestion on the CSX North End Sub, most likely. Also, there's a longish stretch of single track where the CSX "belt line" runs in the middle of the Powhite Parkway. North and southbound Amtrak trains often seem to meet at or near Staples Mill Road station. If a northbound is late, due to the single track the southbound will be belayed as well, since he'll most likely hold at the station for the northbound to clear. That, of course, leads to further delays.

I thought it was 100% double track from the Acca wye to Appomattox River bridge in Petersburg. Does CSX keep all Amtrak trains on only one track south of Acca to the James River bridge?