Greetings dear wireguards!

First of all - happy 2018!

I have a quick question:

I am running wireguard on ubuntu 16.04 server and LEDE on router. When I
have everything set up on the router - I decided to upgrade to a newer
version of LEDE. So I did, and then my router would not connect to the
server anymore (although settings have been saved) until I issue a command
on the server:
wg-quick down wg0 && wg-quick up wg0

Then the router automatically connects without an issue. Before that - the
server would not accept a connection from the router, there are no dmesg
errors, no errors whatsoever on both sides. It simply doesn't show a
handshake on the server, and the router sends packets, but receives 0
packets.

Is there an easier way to fix that issue, so a restart on the server would
not be necessary every time an upgrade on the router is made? Or am I
missing something obvious (quite possible lol) that resolves that issue?

Thank you so much!
Tony.