Here's the transition from the Preliminary Survey phase to the Orbital A phase in the Bennu-centric mean ecliptic and equinox of J2000 reference frame (Bennu north pole is almost exactly aligned with the -Z axis).

After the M7P maneuver (Dec 15), the spacecraft performed the following maneuvers:

#	Burn time	DV	Dt	a
M1A	2018-12-19 17:00:00.000	275.0	34.849	7.89
M2A	2018-12-29 17:00:00.000	149.6	19.092	7.83
M3A	2018-12-31 19:43:56.840	60.0	7.959	7.54

The popup label shows the date, the radius vector (m) and the spacecraft orbital speed (mm/s).

Here's the same as above, but with a different view to show that the spacecraft orbital plane does not pass through the center of Bennu (see next graph).

The popup label shows the date, the radius vector (m), the altitude above Bennu (m) and the spacecraft orbital speed (mm/s).

The graph shows all the orbits of this phase in the Bennu-centric Sun-North reference frame.
This view clearly shows that the s/c orbits "behind" the terminator.

#	Burn time	DV
1	2019-01-03 15:26:49.385	148.2
2	2019-01-08 15:01:12.778	19.8
3	2019-01-10 14:09:12.171	38.1
4	2019-01-15 14:09:46.419	46.5
5	2019-01-17 14:09:27.512	28.5
6	2019-01-22 14:10:01.756	72.1
7	2019-01-24 14:09:27.494	101.6
8	2019-01-29 14:09:54.135	93.9
9	2019-01-31 23:58:50.815	18.3
10	2019-02-05 14:09:33.957	11.7
11	2019-02-07 14:09:15.030	16.9
12	2019-02-12 14:16:32.059	23.8
13	2019-02-14 14:09:18.758	11.5
14	2019-02-19 14:09:45.362	23.9
15	2019-02-21 14:09:31.189	43.6
16	2019-02-26 14:09:42.462	38.8
17	2019-02-28 14:11:05.931	78.3

To maintain that orbit, the s/c needed 17 micro-maneuvers (the NAIF's data files report the maneuvers as impulsive). The blue lines represent the DeltaV vectors of those micro-maneuvers. The tail of the vector touches the orbit and represents the s/c position at the instant shown by the blue popup label. The label also shows the sequential number of the maneuver and the DeltaV in µm/s.
For comparison, consider that the largest of the maneuvers (#1) is about 350 times smaller than the average orbital speed.

Here's the same graph as above, but in the Bennu-centric mean ecliptic and equinox of J2000 reference frame.

The graph shows that the s/c precesses to keep its orbital plane almost exactly perpendicular to the Sun-Bennu vector.