My ElasticBeanstalk environment (running a PHP Laravel application) seems to keep terminating instances and re-adding instances, and in the logs, the below seems to be the pattern, as if it's trying to do something with platform-engine.zip but failing or locking up at some point without completing.
<13>Sep 21 08:42:29 [eb-cfn-init]: [2022-09-21T08:42:29.004Z] Completed executing cfn_init.
<13>Sep 21 08:42:29 [eb-cfn-init]: [2022-09-21T08:42:29.013Z] finished _OnInstanceBoot
<13>Sep 21 08:42:29 [eb-cfn-init]: --2022-09-21 08:42:29-- https://elasticbeanstalk-platform-assets-eu-west-2.s3.eu-west-2.amazonaws.com/stalks/eb_php81_amazon_linux_2_1.0.1799.0_20220826002123/lib/platform-engine.zip
<13>Sep 21 08:42:29 [eb-cfn-init]: Resolving elasticbeanstalk-platform-assets-eu-west-2.s3.eu-west-2.amazonaws.com (elasticbeanstalk-platform-assets-eu-west-2.s3.eu-west-2.amazonaws.com)... 52.95.150.134
<13>Sep 21 08:42:29 [eb-cfn-init]: Connecting to elasticbeanstalk-platform-assets-eu-west-2.s3.eu-west-2.amazonaws.com (elasticbeanstalk-platform-assets-eu-west-2.s3.eu-west-2.amazonaws.com)|52.95.150.134|:443... connected.
<13>Sep 21 08:42:29 [eb-cfn-init]: HTTP request sent, awaiting response... 200 OK
<13>Sep 21 08:42:29 [eb-cfn-init]: Length: 26789061 (26M) [application/zip]
<13>Sep 21 08:42:29 [eb-cfn-init]: Saving to: â/tmp/platform-engine.zipâ
<13>Sep 21 08:42:29 [eb-cfn-init]:
<13>Sep 21 08:42:29 [eb-cfn-init]: 0K .......... .......... .......... .......... .......... 0% 7.95M 3s
<13>Sep 21 08:42:29 [eb-cfn-init]: 50K .......... .......... .......... .......... .......... 0% 7.81M 3s
<13>Sep 21 08:42:29 [eb-cfn-init]: 100K .......... .......... .......... .......... .......... 0% 5.67M 4s
<13>Sep 21 08:42:29 [eb-cfn-init]: 150K .......... .......... .......... .......... .......... 0% 7.58M 4s
<13>Sep 21 08:42:29 [eb-cfn-init]: 200K .......... .......... .......... .......... .......... 0% 130M 3s
<13>Sep 21 08:42:29 [eb-cfn-init]: 250K .......... .......... .......... .......... .......... 1% 6.94M 3s
<13>Sep 21 08:42:29 [eb-cfn-init]: 300K .......... .......... .......... .......... .......... 1% 116M 3s
<13>Sep 21 08:42:29 [eb-cfn-init]: 350K .......... .......... .......... .......... .......... 1% 7.74M 3s
<13>Sep 21 08:42:29 [eb-cfn-init]: 400K .......... .......... .......... .......... .......... 1% 165M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 450K .......... .......... .......... .......... .......... 1% 7.54M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 500K .......... .......... .......... .......... .......... 2% 125M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 550K .......... .......... .......... .......... .......... 2% 7.79M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 600K .......... .......... .......... .......... .......... 2% 165M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 650K .......... .......... .......... .......... .......... 2% 7.27M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 700K .......... .......... .......... .......... .......... 2% 6.99M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 750K .......... .......... .......... .......... .......... 3% 216M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 800K .......... .......... .......... .......... .......... 3% 6.73M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 850K .......... .......... .......... .......... .......... 3% 221M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 900K .......... .......... .......... .......... .......... 3% 5.54M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 950K .......... .......... .......... .......... .......... 3% 220M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 1000K .......... .......... .......... .......... .......... 4% 5.30M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 1050K .......... .......... .......... .......... .......... 4% 229M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 1100K .......... .......... .......... .......... .......... 4% 172M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 1150K .......... .......... .......... .......... .......... 4% 5.39M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 1200K .......... .......... .......... .......... .......... 4% 5.41M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 1250K .......... .......... .......... .......... .......... 4% 208M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 1300K .......... .......... .......... .......... .......... 5% 5.34M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 1350K .......... .......... .......... .......... .......... 5% 182M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 1400K .......... .......... .......... .......... .......... 5% 4.53M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 1450K .......... .......... .......... .......... .......... 5% 194M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 1500K .......... .......... .......... .......... .......... 5% 243M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 1550K .......... .......... .......... .......... .......... 6% 50.5M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 1600K .......... .......... .......... .......... .......... 6% 5.23M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 1650K .......... .......... .......... .......... .......... 6% 211M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 1700K .......... .......... .......... .......... .......... 6% 136M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 1750K .......... .......... .......... .......... .......... 6% 55.0M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 1800K .......... .......... .......... .......... .......... 7% 152M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 1850K .......... .......... .......... .......... .......... 7% 5.53M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 1900K .......... .......... .......... .......... .......... 7% 222M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 1950K .......... .......... .......... .......... .......... 7% 122M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 2000K .......... .......... .......... .......... .......... 7% 65.4M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 2050K .......... .......... .......... .......... .......... 8% 166M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 2100K .......... .......... .......... .......... .......... 8% 161M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 2150K .......... .......... .......... .......... .......... 8% 5.48M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 2200K .......... .......... .......... .......... .......... 8% 217M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 2250K .......... .......... .......... .......... .......... 8% 111M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 2300K .......... .......... .......... .......... .......... 8% 5.32M 2s
<13>Sep 21 08:42:29 [eb-cfn-init]: 2350K .......... .......... .......... .......... .......... 9% 260M 2s
<13>Sep 21 08:42:30 [eb-cfn-init]: 2400K .......... .......... .......... .......... .......... 9% 130M 2s
<13>Sep 21 08:42:30 [eb-cfn-init]: 2450K .......... .......... .......... .......... .......... 9% 233M 2s
<13>Sep 21 08:42:30 [eb-cfn-init]: 2500K .......... .......... .......... .......... .......... 9% 68.0M 2s
<13>Sep 21 08:42:30 [eb-cfn-init]: 2550K .......... .......... .......... .......... .......... 9% 4.22M 2s
<13>Sep 21 08:42:30 [eb-cfn-init]: 2600K .......... .......... .......... .......... .......... 10% 212M 2s
<13>Sep 21 08:42:30 [eb-cfn-init]: 2650K .......... .......... .......... .......... .......... 10% 110M 2s
<13>Sep 21 08:42:30 [eb-cfn-init]: 2700K .......... .......... .......... .......... .......... 10% 237M 2s
and so on to about 66 or 67% where it gets stuck.