Script with check update broken in 6.26 or 6.27

RouterOS Scripting
1

I have script with check for update

/system package update check-for-updates
:delay 1s;
:local sysname [/system identity get name];
:local sysver [/system package get system version];
:local newver [/system package update get latest-version];
:local routeros;
:set routeros "RouterOS version: $sysver";
:if ($sysver != $newver) do= {:set routeros ($routeros . "\nUpdate avalible: $newver");}

After upgrade from 6.25 to 6.27 I don’t recive mail with backups. After debug this script I see, that commands begin with

/system package update

don’t run next commands.
How I can check new version in script?

Device: RB751G-2HnD
RouterOS: 7.27

2

Fixed script

/system package update check-for-updates once
:delay 1s;
:local sysname [/system identity get name];
:local sysver [/system package get system version];
:local newver ([/system package update check-for-updates once as-value ] -> "latest-version")
:local routeros;
:set routeros "RouterOS version: $sysver";
:if ($sysver != $newver) do= {:set routeros ($routeros . "\nUpdate avalible: $newver");}