I suspect what you are seeing is the preferred cores. With TVB/OCTVB (thermal velocity boost/overclocking thermal velocity boost) those can boost higher than the other cores.

From my 12900ks (its a boosted 12900k)
Core 6-7 is rated for 5.5ghz.

Freq MHz DTS C VID mv PC Eff Fr UCcode 0x1f VR Volt Limit 2500
----------------------------------------------------
800 24 1307 52 517 Uncore 3600 IA AC LL 0.5999
800 20 1282 52 47 Power 23.465 IA DC LL 1.0996
800 20 1314 52 70 Current Limit 0.0000 SA AC LL 0.0000
800 20 1308 52 69 iccmax 1023 SA DC LL 0.0000
800 20 1303 52 88 PL1 32760 iccmax dis True
800 18 1293 52 69 PL2 32760 TAU 33
800 20 1286 55 39 Memory 5200 PPP_OVR True
800 22 730 55 37 EE_Turbo_Dis True RTH_Dis True
800 22 1377 40 60 Dis_Ring_EE False HWGuidedSch True
800 22 1172 40 73 IA_CEP_Dis True Dynamic_Mem True
Full_Range_Multi False SA_Freq_OVR False
TSC_Dis_HW False Banding_Ratio 0
PVD_Ratio_thresh 0 SA_CEP_Dis True
FLL OC Mode 3

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Core Voltage Adapt 0 Ring Voltage Adapt 0 Core PLL V 900
Core Voltage Offset 0 Ring Voltage Offset 0 Ring PLL V 900
L2 Voltage Adapt 0 L2 Voltage Offset 0 AVX512 Offset 0
SA Voltage Offset 0 Ring VID 0 MC PLL V 900
AVX Offset 0 AVX2 V Guardband 0 AVX512 V Guardband 0
SA Voltage Manual 1150

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Turbo Ratio Limit 55, 55, 52, 52, 52, 52, 52, 52 Core OCMB Max Ratio 0 Ring Min Ratio 8
Turbo Limit Cores 1, 2, 3, 4, 5, 6, 7, 8 Ring OCMB Max Ratio 0 Ring Max Ratio 47
Atom Ratio Limit 40, 40, 40, 40, 40, 40, 40, 40 Atom Limit Cores 255, 255, 255, 255, 255, 255, 255, 255Atom OCMB Max Ratio 0
OS Max Ratio 34 HWP Min Ratio 43 HWP Max Ratio 255
Max Possible Core 40 Max Possible Ring 47 UCLK 2600

Num cores: 24
Using RDTSC to measure time: false
Num round trips per samples: 5000
Num samples: 300
Showing latency=round-trip-time/2 in nanoseconds:

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
0
1 0±0
2 37±6 36±6
3 31±6 37±6 5±5
4 26±6 26±6 26±6 26±6
5 26±6 31±6 26±6 31±6 5±5
6 31±6 31±6 36±6 31±6 26±6 21±6
7 31±6 31±6 31±6 31±6 26±6 26±6 5±5
8 31±6 31±6 31±6 31±6 26±6 26±6 31±6 26±6
9 36±6 31±6 31±6 31±6 26±6 26±6 26±6 26±6 5±5
10 31±6 36±6 31±6 26±6 26±6 21±6 26±6 31±6 26±6 31±6
11 31±6 36±6 31±6 36±6 26±6 26±6 31±6 31±6 36±6 31±6 5±5
12 31±6 36±6 31±6 42±6 26±6 31±6 31±6 37±6 31±6 37±6 31±6 36±6
13 36±6 37±6 42±6 36±6 26±6 26±6 31±6 31±6 31±6 31±6 31±6 31±6 5±5
14 31±6 36±6 37±6 36±6 31±6 26±6 36±6 31±6 36±6 31±6 36±6 31±6 31±6 36±6
15 31±6 31±6 31±6 31±6 26±6 26±6 36±6 31±6 31±6 31±6 31±6 31±6 31±6 31±6 0±0
16 42±6 42±6 42±6 42±6 31±6 31±6 37±6 36±6 36±6 42±6 37±6 36±6 36±6 36±6 37±6 37±6
17 42±6 42±6 36±6 42±6 31±6 36±6 37±6 36±6 36±6 37±6 36±6 37±6 36±6 36±6 36±6 37±6 47±6
18 42±6 42±6 42±6 42±6 31±6 31±6 37±6 36±6 37±6 36±6 42±6 36±6 37±6 36±6 36±6 36±6 47±6 52±6
19 42±6 42±6 42±6 37±6 31±6 31±6 36±6 37±6 36±6 36±6 37±6 37±6 36±6 36±6 42±6 37±6 52±6 47±6 47±6
20 42±6 42±6 42±6 36±6 37±6 31±6 37±6 36±6 37±6 36±6 36±6 42±6 37±6 36±6 36±6 42±6 42±6 42±6 42±6 42±6
21 42±6 37±6 42±6 42±6 31±6 31±6 37±6 36±6 42±6 36±6 37±6 36±6 37±6 37±6 36±6 36±6 42±6 42±6 42±6 42±6 47±6
22 42±6 42±6 42±6 36±6 36±6 31±6 36±6 37±6 36±6 37±6 36±6 36±6 36±6 37±6 36±6 42±6 42±6 42±6 42±6 42±6 47±6 52±6
23 36±6 42±6 42±6 42±6 31±6 31±6 37±6 36±6 37±6 42±6 36±6 36±6 37±6 42±6 36±6 36±6 42±6 42±6 42±6 42±6 52±6 47±6 47±6

Min latency: 0.0ns ±0.0 cores: (1,0)
Max latency: 52.3ns ±16.3 cores: (23,20)
Mean latency: 34.6ns