[Bug]: Version checker show current version after update in web GUI

⚠️ This issue respects the following points: ⚠️

• This is a bug, not a question or a configuration/webserver/proxy issue.
• This issue is not already reported on Github OR Nextcloud Community Forum (I've searched it).
• Nextcloud Server is up to date. See Maintenance and Release Schedule for supported versions.
• I agree to follow Nextcloud's Code of Conduct.

Bug description

Noticed on update from 25.0.10.2 => 25.0.13.3 and 25.0.13.3 => 25.0.13.4 (latest patch version atm)

updater.log file shows correct version to update to (next major, 26.0.9.2)

Thoughts after research:

• Opcache might cache old php version and use it for the request - in this case seems to be configured correctly, so shouldn't be the reason;
• Value for web-interface is cached for 30 minutes maximum if check is called, but there might be something that prevents it from refresh.

Code sources:
updater - version check:
https://github.com/nextcloud/updater/blob/master/lib/Updater.php#L126

admin page - vesion check:
https://github.com/nextcloud/server/blob/master/lib/private/Updater/VersionCheck.php#L52

Issue posted to track it, as may happens sometime on more recent versions (27.1.4.1)

Steps to reproduce

1. Perform update via updater.phar
2. Check admin page to see if that happens

Expected behavior

Web GUI should show correct version to update to (next major, 26.0.9.2 in that case)

Installation method

Official All-in-One appliance

Nextcloud Server version

26

Operating system

None

PHP engine version

PHP 8.0

Web server

None

Database engine version

None

Is this bug present after an update or on a fresh install?

Updated from a MINOR version (ex. 22.1 to 22.2)

Are you using the Nextcloud Server Encryption module?

None

What user-backends are you using?

• Default user-backend (database)
• LDAP/ Active Directory
• SSO - SAML
• Other

Configuration report

No response

List of activated Apps

No response

Nextcloud Signing status

No response

Nextcloud Logs

No response

Additional info

updater.log:

2023-11-29T14:01:55+0000 <request> [info] releaseChannel: enterprise
2023-11-29T14:01:55+0000 <request> [info] internal version: 25.0.13.4
2023-11-29T14:01:55+0000 <request> [info] updateURL: https://updates.nextcloud.com/customers/<subsciption-key>/?version=25x0x13x4xxxenterprisexx2023-11-23<hash>
2023-11-29T14:01:55+0000 <request> [info] getUpdateServerResponse response: Array
(
    [version] => 26.0.9.2
    [versionstring] => Nextcloud 26.0.9 Enterprise
    [url] => https://download.nextcloud.com/.customers/server/26.0.9-102bdc0d/nextcloud-26.0.9-enterprise.zip
    [web] => https://docs.nextcloud.com/server/26/admin_manual/maintenance/upgrade.html
    [changes] => https://updates.nextcloud.com/changelog_server/?version=26.0.9
    [autoupdater] => 1
    [eol] => 0
    [signature] => <signature>
)

Start with the version-check paths named in lib/Updater.php around line 126 and lib/private/Updater/VersionCheck.php around line 52. Reproduce an update with updater.phar, compare updater.log with the admin page's displayed version, and trace why the web GUI remains stale. Done means the GUI shows the correct next version after an update.