Netgear GS724TP - Drops uplink on when router reboots

Hi all, so I have a small charity that is split into 4 buildings. Each building is uplinked with underground CAT6 armoured cabling back to our main cabinet.

Our main cabinet contains a HP gigabit switch, our router and a few other things. Each building link is plugged into this switch.

Two of our buildings have a Netgear GS724TP switch. They are mainly used for cameras, WiFi etc, so they just need a link back to the main switch for access to the internet etc.

Basically, whenever our Draytek 2860 router is rebooted, both of these switches loose connectivity and require a reboot to come back online. I cannot get to them to troubleshoot what their issue is, but I assume for one reason or another they are disabling the uplink ports back to the main network. Our other buildings have HP equipment and they do not have this issue. Since both Netgear switches in different buildings do the same thing, I can only assume this is some sort of setting that I need to change, perhaps on the ports that are being used for uplink?

Any advice or suggestions are appreciated on this.