DHCP fails after battery goes flat

What problem did you encounter

dhclient (and NetworkManager too) fails when starting the phone after the battery is dead enough for the RTC to reset.

How to reproduce

1. Connect to a host runnig DHCP (can be usb0)
2. Set system date to Wed Dec 31 12:03:03 UTC 2155
3. dhclient -v usb0

What is the actual behaviour?

No IPv4 address on WiFi or usb0 (no way to get system updates from Purism IPv4 servers)

dhclient output:

purism@pureos:~$ sudo dhclient -4 -v usb0
Internet Systems Consortium DHCP Client 4.4.1
Copyright 2004-2018 Internet Systems Consortium.
All rights reserved.
For info, please visit https://www.isc.org/software/dhcp/

Listening on LPF/usb0/1e:4f:b8:42:6c:f3
Sending on   LPF/usb0/1e:4f:b8:42:6c:f3
Sending on   Socket/fallback
DHCPDISCOVER on usb0 to 255.255.255.255 port 67 interval 6
Unable to set up timer: out of range

If you think you have received this message due to a bug rather
than a configuration issue please read the section on submitting
bugs on either our web page at www.isc.org or in the README file
before submitting a bug.  These pages explain the proper
process and the information we find helpful for debugging.

exiting.

What is the expected behaviour?

DHCP is independent of system date.

What hardware are you running on?

Birch

Relevant OS information

Which kernel are you using?

Linux pureos 5.3.0-librem5-h1 #1 (closed) SMP PREEMPT Mon Dec 23 13:31:19 UTC 2019 aarch64 GNU/Linux

Which OS are you using?

Amber

Any other information that may be helpful?

root@pureos:/home/purism# dhclient --version
isc-dhclient-4.4.1