Comment 7 for bug 1537793

Verified the randomness of the installed timer with snapd from proposed by checking the scheduled times in two consecutive installations:

fgimenez@fgimenez-Standard-PC-i440FX-PIIX-1996:~$ apt-cache policy snapd
snapd:
  Installed: 2.0.8
  Candidate: 2.0.8
  Version table:
 *** 2.0.8 500
        500 http://archive.ubuntu.com/ubuntu xenial-proposed/main amd64 Packages
        100 /var/lib/dpkg/status
     2.0.5 500
        500 http://es.archive.ubuntu.com/ubuntu xenial-updates/main amd64 Packages
     2.0.2 500
        500 http://es.archive.ubuntu.com/ubuntu xenial/main amd64 Packages
fgimenez@fgimenez-Standard-PC-i440FX-PIIX-1996:~$ sudo systemctl status snapd.refresh.timer
● snapd.refresh.timer - Timer to automatically refresh installed snaps
   Loaded: loaded (/lib/systemd/system/snapd.refresh.timer; enabled; vendor preset: enabled)
   Active: active (waiting) since lun 2016-06-13 09:13:27 CEST; 9s ago

jun 13 09:13:27 fgimenez-Standard-PC-i440FX-PIIX-1996 systemd[1]: snapd.refresh.timer: Adding 1h 36min 19.904959s random time.
jun 13 09:13:27 fgimenez-Standard-PC-i440FX-PIIX-1996 systemd[1]: Started Timer to automatically refresh installed snaps.
jun 13 09:13:27 fgimenez-Standard-PC-i440FX-PIIX-1996 systemd[1]: snapd.refresh.timer: Adding 4h 41min 2.765543s random time.
jun 13 09:13:27 fgimenez-Standard-PC-i440FX-PIIX-1996 systemd[1]: snapd.refresh.timer: Adding 2h 22min 46.565780s random time.
fgimenez@fgimenez-Standard-PC-i440FX-PIIX-1996:~$ sudo apt-get remove --purge snapd
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
  linux-headers-4.4.0-21 linux-headers-4.4.0-21-generic linux-image-4.4.0-21-generic linux-image-extra-4.4.0-21-generic
Use 'sudo apt autoremove' to remove them.
The following packages will be REMOVED:
  snapd*
0 upgraded, 0 newly installed, 1 to remove and 0 not upgraded.
After this operation, 22,1 MB disk space will be freed.
Do you want to continue? [Y/n]
(Reading database ... 244530 files and directories currently installed.)
Removing snapd (2.0.8) ...
Warning: Stopping snapd.service, but it can still be activated by:
  snapd.socket
Purging configuration files for snapd (2.0.8) ...
dpkg: warning: while removing snapd, directory '/snap' not empty so not removed
dpkg: warning: while removing snapd, directory '/var/snap' not empty so not removed
dpkg: warning: while removing snapd, directory '/var/lib/snapd/snaps' not empty so not removed
dpkg: warning: while removing snapd, directory '/var/lib/snapd/desktop' not empty so not removed
Processing triggers for man-db (2.7.5-1) ...
fgimenez@fgimenez-Standard-PC-i440FX-PIIX-1996:~$ sudo apt-get install snapd
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
  linux-headers-4.4.0-21 linux-headers-4.4.0-21-generic linux-image-4.4.0-21-generic linux-image-extra-4.4.0-21-generic
Use 'sudo apt autoremove' to remove them.
The following NEW packages will be installed:
  snapd
0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded.
Need to get 0 B/4.278 kB of archives.
After this operation, 22,1 MB of additional disk space will be used.
Selecting previously unselected package snapd.
(Reading database ... 244506 files and directories currently installed.)
Preparing to unpack .../archives/snapd_2.0.8_amd64.deb ...
Unpacking snapd (2.0.8) ...
Processing triggers for man-db (2.7.5-1) ...
Setting up snapd (2.0.8) ...
fgimenez@fgimenez-Standard-PC-i440FX-PIIX-1996:~$ sudo systemctl status snapd.refresh.timer
● snapd.refresh.timer - Timer to automatically refresh installed snaps
   Loaded: loaded (/lib/systemd/system/snapd.refresh.timer; enabled; vendor preset: enabled)
   Active: active (waiting) since lun 2016-06-13 09:14:38 CEST; 4s ago

jun 13 09:14:38 fgimenez-Standard-PC-i440FX-PIIX-1996 systemd[1]: snapd.refresh.timer: Adding 47min 42.556120s random time.
jun 13 09:14:38 fgimenez-Standard-PC-i440FX-PIIX-1996 systemd[1]: Started Timer to automatically refresh installed snaps.
jun 13 09:14:38 fgimenez-Standard-PC-i440FX-PIIX-1996 systemd[1]: snapd.refresh.timer: Adding 2h 16min 1.104444s random time.
jun 13 09:14:38 fgimenez-Standard-PC-i440FX-PIIX-1996 systemd[1]: snapd.refresh.timer: Adding 5h 40min 1.839101s random time.