How to reconfigure system without downloads I did not order?

[znavko]

Hello! I have a little incomprehension that make solving a simple task so slow.

I just want to say Guix to mount newly inserted SSD (3rd from all) after every 
start.

I have just edited /root/config-2-disks.conf placing these lines:

(operating-system (host-name "antelope") (timezone "Europe/Moscow") (locale 
"en_US.utf8")
 (bootloader (bootloader-configuration (bootloader grub-efi-bootloader) (target 
"/boot/efi")))
 (file-systems (cons*
 (file-system (device "/dev/sda1") (mount-point "/boot/efi") (type "vfat"))
 (file-system (device "/dev/sda2") (mount-point "/") (type "ext4"))
 (file-system (device "/dev/sdb1") (mount-point "/home/bob/disk1") (type 
"ext4"))
 (file-system (device "/dev/sdc1") (mount-point "/home/bob/disk2") (type 
"ext4"))
 %base-file-systems))
The process of reconfiguration fails every time sometimes on downloading 
linux-libre, sometimes libwnck:
# guix system reconfigure /root/config-2-disks.conf
...
downloading from 
https://ci.guix.gnu.org/nar/lzip/4v3c26b84jgxz0gar0n75dy47hxl213y-libmbim-1.20.2
 ...
 libmbim-1.20.2 262KiB 700KiB/s 00:00 [##################] 100.0%

downloading from 
https://ci.guix.gnu.org/nar/lzip/jb5rq36y60dam3h0bmwp1g7hcaqnbfgn-ffmpeg-4.3.1 
...
 ffmpeg-4.3.1 8.8MiB 991KiB/s 00:09 [##################] 100.0%

downloading from 
https://ci.guix.gnu.org/nar/lzip/k9rlni2yafzz79kqm4b0rx7r0h0bhq70-libqmi-1.24.14
 ...
 libqmi-1.24.14 1.5MiB 975KiB/s 00:02 [##################] 100.0%

guix substitute: error: connect: Connection timed out
substitution of /gnu/store/r28zc1yn6aw5jnij6jap45lr4fnvd7hs-alsa-plugins-1.2.2 
failed
killing process 3824
guix system: error: some substitutes for the outputs of derivation 
`/gnu/store/zkynj525l0xvy8j3j6x7lb6k7da98qsr-alsa-plugins-1.2.2.drv' failed 
(usually happens due to networking issues); try `--fallback' to build 
derivation from source
root@antelope ~# guix system reconfigure /root/config-2-disks.conf
46.1 MB will be downloaded
downloading from 
https://ci.guix.gnu.org/nar/lzip/smjm2hv2lwi1hhb9kzkkras55qzl6yf8-linux-libre-headers-5.4.20
 ...
 linux-libre-headers-5.4.20 1.0MiB 276KiB/s 00:04 [##################] 100.0%
# guix system reconfigure /root/config-2-disks.conf
...
downloading from 
https://ci.guix.gnu.org/nar/lzip/f6biy2lp9b5nhpr1h94npbfngjhqayxr-startup-notification-0.12
 ...
 startup-notification-0.12 33KiB 2.9MiB/s 00:00 [##################] 100.0%

downloading from 
https://ci.guix.gnu.org/nar/lzip/867mz9gqk8x2p0b58z0zkys65pghwdwl-upower-0.99.11
 ...
 upower-0.99.11 179KiB 630KiB/s 00:00 [##################] 100.0%

guix substitute: error: connect: Connection timed out
substitution of /gnu/store/84ys8zyxzn231q9y27kysxyyzy41kd14-libwnck-3.32.0 
failed
killing process 4220
guix system: error: some substitutes for the outputs of derivation 
`/gnu/store/n8sm20aswfjqscp70p4njvj50h5vnk8v-thunar-1.8.16.drv' failed (usually 
happens due to networking issues); try `--fallback' to build derivation from 
source
root@antelope ~# guix system reconfigure --help
Usage: guix system [OPTION ...] ACTION [ARG ...] [FILE]
Build the operating system declared in FILE according to ACTION.
Some ACTIONS support additional ARGS.
I am sorry. How to prevent the process of system upgrade and just remain things 
as they are but only adding new disk to my system?