Cirrus CI for macOS branches 16 and 15 broken

The Cirrus CI for REL_16_STABLE and REL_15_STABLE for macOS is
apparently broken right now. Here is a log example:

[13:57:11.305] sh src/tools/ci/ci_macports_packages.sh \
[13:57:11.305] ccache \
[13:57:11.305] icu \
[13:57:11.305] kerberos5 \
[13:57:11.305] lz4 \
[13:57:11.305] meson \
[13:57:11.305] openldap \
[13:57:11.305] openssl \
[13:57:11.305] p5.34-io-tty \
[13:57:11.305] p5.34-ipc-run \
[13:57:11.305] python312 \
[13:57:11.305] tcl \
[13:57:11.305] zstd
[13:57:11.325] macOS major version: 14
[13:57:12.554] MacPorts package URL:
https://github.com/macports/macports-base/releases/download/v2.9.3/MacPorts-2.9.3-14-Sonoma.pkg
[14:01:37.252] installer: Package name is MacPorts
[14:01:37.252] installer: Installing at base path /
[14:01:37.252] installer: The install was successful.
[14:01:37.257]
[14:01:37.257] real 4m23.837s
[14:01:37.257] user 0m0.385s
[14:01:37.257] sys 0m0.339s
[14:01:37.282] macportsuser root
[14:01:37.431] Error: /opt/local/bin/port: Failed to initialize
MacPorts, sqlite error: attempt to write a readonly database (8) while
executing query: CREATE INDEX registry.snapshot_file_id ON
snapshot_files(id)
[14:01:37.599] Error: No ports matched the given expression

REL_17_STABLE and up are working.

I know there have been some changes recently to manage the OS version
change. Are these older branches expected to work?