Grapheneos fails to boot with avbroot-patched ota

This is a recent change either with aosp or avbroot as I had this working fine in early march. Trying to update to 2026041200 on the pixel 9a, boot fails on the GOS logo screen. After a reboot it boots into recovery, saying "cannot load system" and offering to factory reset. No console-ramoops-0 or any other files in /sys/fs/pstore. The command I used to generate the OTA: avbroot ota patch \ --input tegu-ota_update-2026042100.zip \ --key-avb ~/Documents/otakeys/avb.key \ --key-ota ~/Documents/otakeys/avb.key \ --cert-ota ~/Documents/otakeys/ota.crt \ --rootless Output of cat /data/misc/update_engine_log/update_engine.20260423-184255: [0423/184255.783353] [INFO:main.cc(53)] Using temp dir /data/misc/update_engine/tmp [0423/184255.783703] [INFO:main.cc(62)] A/B Update Engine starting [0423/184255.796885] Error opening trace file: No such file or directory (2) [0423/184255.798675] [INFO:BootControlClient.cpp(402)] Using AIDL version of IBootControl [0423/184255.798984] [INFO:boot_control_android.cc(64)] Loaded boot control hal. [0423/184255.812201] [ERROR:update_attempter_android.cc(1094)] prefs_->GetInt64(kPrefsPreviousSlot, &previous_slot) failed. [0423/184255.812401] [INFO:update_attempter_android.cc(227)] OTAResult::NOT_ATTEMPTED [0423/184255.869204] [INFO:update_attempter_android.cc(987)] Clearing update complete marker. [0423/184255.869549] [INFO:update_attempter_android.cc(1511)] Scheduling CleanupPreviousUpdateAction. [0423/184255.869943] [INFO:action_processor.cc(51)] ActionProcessor: starting CleanupPreviousUpdateAction [0423/184255.870175] [INFO:cleanup_previous_update_action.cc(151)] Starting/resuming CleanupPreviousUpdateAction [0423/184305.911909] [INFO:cleanup_previous_update_action.cc(192)] Boot completed, waiting on markBootSuccessful() [0423/184305.920726] [INFO:snapshot.cpp(4569)] EnsureMetadataMounted does nothing in Android mode. [0423/184305.922663] [INFO:snapshot_stats.cpp(40)] Read merge statistics file failed: No such file or directory [0423/184305.938796] [INFO:cleanup_previous_update_action.cc(291)] Waiting for any previous merge request to complete. This can take up to several minutes. [0423/184305.944317] [INFO:boot_config.cpp(46)] [libfstab] Using Android DT directory /proc/device-tree/firmware/android/ [0423/184305.967386] [WARN:snapshot.cpp(2125)] Detected rollback, cancelling unverified update. [0423/184306.054387] [INFO:delta_performer.cc(1470)] Resetting recorded hash for prepared partitions. [0423/184306.056639] [INFO:snapshot.cpp(361)] Removing all update state. [0423/184307.998899] Waited one second for gsiservice (is service started? Number of threads started in the threadpool: 1. Are binder threads started and available?) [0423/184308.004077] [INFO:snapshot.cpp(3239)] Successfully unmapped snapshot product_b [0423/184308.010427] [INFO:snapshot.cpp(3239)] Successfully unmapped snapshot system_b [0423/184308.014166] [INFO:snapshot.cpp(3239)] Successfully unmapped snapshot system_dlkm_b [0423/184308.017323] [INFO:snapshot.cpp(3239)] Successfully unmapped snapshot vendor_dlkm_b [0423/184308.020100] [INFO:snapshot.cpp(3239)] Successfully unmapped snapshot system_ext_b [0423/184308.022645] [INFO:snapshot.cpp(3239)] Successfully unmapped snapshot vendor_b [0423/184308.032667] [INFO:BootControlClient.cpp(402)] Using AIDL version of IBootControl [0423/184308.039955] [INFO:snapshot.cpp(1550)] CheckMergeState for snapshots returned: Cancelled [0423/184308.119714] [INFO:delta_performer.cc(1470)] Resetting recorded hash for prepared partitions. [0423/184308.120303] [INFO:snapshot.cpp(361)] Removing all update state. [0423/184308.129932] [INFO:snapshot.cpp(1515)] ProcessUpdateState handling state: Cancelled [0423/184308.130673] [INFO:cleanup_previous_update_action.cc(133)] Stopping/suspending/completing CleanupPreviousUpdateAction [0423/184308.132762] [INFO:cleanup_previous_update_action.cc(542)] Reporting merge stats: Cancelled in 1271ms (resumed 0 times), using 0 bytes of COW image. [0423/184308.134111] [INFO:cleanup_previous_update_action.cc(133)] Stopping/suspending/completing CleanupPreviousUpdateAction [0423/184308.134934] [INFO:action_processor.cc(116)] ActionProcessor: finished last action CleanupPreviousUpdateAction with code ErrorCode::kSuccess [0423/184308.135538] [INFO:update_attempter_android.cc(735)] Processing Done. [0423/184308.157646] [INFO:dynamic_partition_control_android.cc(350)] Destroying [] from device mapper [0423/184308.158392] [INFO:dynamic_partition_control_android.cc(354)] UnmapAllPartitions done [0423/184308.158989] [INFO:dynamic_partition_control_android.cc(359)] SnapshotManager released [0423/184308.159442] [INFO:update_attempter_android.cc(987)] Clearing update complete marker. [0423/184308.160074] [INFO:update_attempter_android.cc(884)] Terminating cleanup previous update.