From experience I know, that this is an exceptional event. When it occurs, usually only a single contact is affected.
Possibly someone has an idea explaining what I have seen.
Following a section from my verbose log:
24.04.2021 18:51:28: value update from kad contact IP=2.36.195.84 (UDP:4772 -> UDP:10371) 24.04.2021 18:51:54: value update from kad contact IP=218.92.77.238 (UDP:4772 -> UDP:5829) 24.04.2021 18:51:54: value update from kad contact IP=109.75.93.163 (UDP:4772 -> UDP:34895) 24.04.2021 18:52:02: value update from kad contact IP=122.238.187.24 (UDP:4772 -> UDP:20226) 24.04.2021 18:52:22: value update from kad contact IP=84.123.101.156 (UDP:4772 -> UDP:23881) 24.04.2021 18:54:10: value update from kad contact IP=123.192.81.111 (UDP:4772 -> UDP:20788) 24.04.2021 18:55:31: value update from kad contact IP=109.52.207.157 (UDP:4692 -> UDP:7271) 24.04.2021 18:55:41: value update from kad contact IP=171.113.164.239 (UDP:4692 -> UDP:22991) 24.04.2021 18:55:41: value update from kad contact IP=42.80.217.50 (UDP:4692 -> UDP:23277) 24.04.2021 18:55:57: value update from kad contact IP=223.73.28.33 (UDP:4692 -> UDP:36577) 24.04.2021 18:56:03: value update from kad contact IP=92.149.154.174 (UDP:4692 -> UDP:4671) 24.04.2021 18:56:29: value update from kad contact IP=83.51.28.33 (UDP:4692 -> UDP:55308) 24.04.2021 18:57:12: value update from kad contact IP=87.8.67.36 (UDP:4692 -> UDP:24336) 24.04.2021 18:57:37: value update from kad contact IP=84.108.100.146 (UDP:4692 -> UDP:54979) 24.04.2021 18:58:11: value update from kad contact IP=111.246.92.244 (UDP:4692 -> UDP:5028) 24.04.2021 18:58:47: value update from kad contact IP=83.42.4.146 (UDP:4692 -> UDP:37401) 24.04.2021 19:00:06: value update from kad contact IP=223.240.53.191 (UDP:4692 -> UDP:49608) 24.04.2021 19:00:23: value update from kad contact IP=182.131.214.117 (UDP:4692 -> UDP:20704) 24.04.2021 19:00:25: value update from kad contact IP=110.87.164.238 (UDP:4692 -> UDP:40532) 24.04.2021 19:00:28: value update from kad contact IP=80.230.7.192 (UDP:4692 -> UDP:4672) 24.04.2021 19:00:38: value update from kad contact IP=212.231.62.168 (UDP:4692 -> UDP:4672) 24.04.2021 19:00:42: value update from kad contact IP=70.95.212.2 (UDP:4692 -> UDP:5153) 24.04.2021 19:00:47: value update from kad contact IP=149.74.38.114 (UDP:4692 -> UDP:4672) 24.04.2021 19:00:47: value update from kad contact IP=83.165.28.26 (UDP:4692 -> UDP:64671) 24.04.2021 19:00:54: value update from kad contact IP=88.24.251.103 (UDP:4692 -> UDP:37867) 24.04.2021 19:01:09: value update from kad contact IP=85.53.84.93 (UDP:4692 -> UDP:1985) 24.04.2021 19:01:36: value update from kad contact IP=175.161.71.78 (UDP:4692 -> UDP:6266) 24.04.2021 19:02:25: value update from kad contact IP=92.21.70.5 (UDP:4692 -> UDP:37034) 24.04.2021 19:02:51: value update from kad contact IP=95.123.127.222 (UDP:4692 -> UDP:63017) 24.04.2021 19:02:51: value update from kad contact IP=79.32.132.251 (UDP:4692 -> UDP:30597) 24.04.2021 19:03:13: value update from kad contact IP=81.0.37.38 (UDP:4692 -> UDP:36427) 24.04.2021 19:03:28: value update from kad contact IP=188.76.78.21 (UDP:4692 -> UDP:19502) 24.04.2021 19:03:29: value update from kad contact IP=36.237.105.74 (UDP:4692 -> UDP:4672) 24.04.2021 19:03:40: value update from kad contact IP=87.70.22.103 (UDP:4692 -> UDP:5672) 24.04.2021 19:03:46: value update from kad contact IP=96.255.93.55 (UDP:4692 -> UDP:47116) 24.04.2021 19:03:53: value update from kad contact IP=123.13.221.170 (UDP:4692 -> UDP:5811) 24.04.2021 19:04:13: value update from kad contact IP=176.128.81.9 (UDP:4692 -> UDP:32439) 24.04.2021 19:04:14: value update from kad contact IP=90.12.228.216 (UDP:4692 -> UDP:5192) 24.04.2021 19:04:19: value update from kad contact IP=80.101.109.68 (UDP:4692 -> UDP:6789) 24.04.2021 19:04:28: value update from kad contact IP=85.53.15.69 (UDP:4692 -> UDP:52131) 24.04.2021 19:04:32: value update from kad contact IP=37.163.28.151 (UDP:4692 -> UDP:30504) 24.04.2021 19:04:37: value update from kad contact IP=109.115.236.127 (UDP:4692 -> UDP:4672) 24.04.2021 19:05:02: value update from kad contact IP=213.177.200.98 (UDP:4692 -> UDP:14303) 24.04.2021 19:05:35: value update from kad contact IP=94.73.43.138 (UDP:4692 -> UDP:13803) 24.04.2021 19:05:36: value update from kad contact IP=123.139.176.158 (UDP:4692 -> UDP:2924) 24.04.2021 19:05:46: value update from kad contact IP=79.156.195.138 (UDP:4692 -> UDP:31799) 24.04.2021 19:05:53: value update from kad contact IP=79.47.128.88 (UDP:4692 -> UDP:5410) 24.04.2021 19:06:18: value update from kad contact IP=93.36.181.127 (UDP:4692 -> UDP:14201) 24.04.2021 19:06:30: value update from kad contact IP=1.29.25.190 (UDP:4692 -> UDP:16628) 24.04.2021 19:06:52: value update from kad contact IP=86.121.119.84 (UDP:4692 -> UDP:6112) 24.04.2021 19:06:54: value update from kad contact IP=220.165.108.47 (UDP:4692 -> UDP:5120) 24.04.2021 19:08:39: value update from kad contact IP=131.93.143.187 (UDP:4672 -> UDP:11082) 24.04.2021 19:09:10: value update from kad contact IP=1.200.15.220 (UDP:4672 -> UDP:11675) 24.04.2021 19:10:08: value update from kad contact IP=101.93.81.64 (UDP:4672 -> UDP:46251) 24.04.2021 19:10:40: value update from kad contact IP=221.223.97.179 (UDP:4672 -> UDP:3230) 24.04.2021 19:10:50: value update from kad contact IP=108.214.192.46 (UDP:4672 -> UDP:6093) 24.04.2021 19:10:53: value update from kad contact IP=79.147.195.128 (UDP:4672 -> UDP:44265) 24.04.2021 19:10:57: value update from kad contact IP=124.13.76.213 (UDP:4672 -> UDP:22342) 24.04.2021 19:11:01: value update from kad contact IP=125.78.1.225 (UDP:4672 -> UDP:34029) 24.04.2021 19:11:10: value update from kad contact IP=176.85.16.176 (UDP:4672 -> UDP:6883) 24.04.2021 19:11:10: value update from kad contact IP=90.92.125.242 (UDP:4672 -> UDP:40672) 24.04.2021 19:11:15: value update from kad contact IP=80.30.237.152 (UDP:4672 -> UDP:7020) 24.04.2021 19:11:29: value update from kad contact IP=79.36.95.178 (UDP:4672 -> UDP:1024) 24.04.2021 19:11:53: value update from kad contact IP=178.237.234.154 (UDP:4672 -> UDP:1696) 24.04.2021 19:12:25: value update from kad contact IP=95.120.207.249 (UDP:4672 -> UDP:1985) 24.04.2021 19:12:38: value update from kad contact IP=37.14.51.24 (Version:4 -> Version:3) 24.04.2021 19:12:57: value update from kad contact IP=79.36.95.178 (UDP:4672 -> UDP:5643) 24.04.2021 19:13:24: value update from kad contact IP=139.227.242.113 (UDP:4672 -> UDP:6658) 24.04.2021 19:13:48: value update from kad contact IP=78.227.247.119 (UDP:4672 -> UDP:62313) 24.04.2021 19:14:09: value update from kad contact IP=84.193.50.177 (UDP:4672 -> UDP:30444) 24.04.2021 19:14:23: value update from kad contact IP=223.71.54.240 (UDP:4672 -> UDP:41176) 24.04.2021 19:14:27: value update from kad contact IP=83.215.178.129 (UDP:4672 -> UDP:51529) 24.04.2021 19:14:47: value update from kad contact IP=221.196.154.34 (UDP:4672 -> UDP:4178) 24.04.2021 19:14:59: value update from kad contact IP=185.77.217.104 (UDP:4672 -> UDP:1001) 24.04.2021 19:15:43: value update from kad contact IP=151.63.78.101 (UDP:4672 -> UDP:57137) 24.04.2021 19:15:56: value update from kad contact IP=95.174.66.252 (UDP:4672 -> UDP:7890) 24.04.2021 19:15:57: value update from kad contact IP=95.120.37.124 (TCP:4662 -> TCP:4665) 24.04.2021 19:16:05: value update from kad contact IP=177.54.157.216 (UDP:4672 -> UDP:27977)