Unable to upgrade router firmware

[#1]

I have been trying to upgrade my TGV 585v8 software. I have had loads of problems, but managed to get through to the upgrade state.
I got to the 'starting upgrade' section, it then slowed to a crawl at 10% and 10%. I left it, and after 2 hours it finally completed....or so i thought. Then I got a message that the upgrade was unsuccessful and 'click back to retry' or do something ( I can't remember what, but I had no idea what it meant) to the power supply.
Thankfully, I still have access to the router so nothing lost, but any suggestions on how to upgrade now?

[#2]

It should only take a few minutes for the new software to upload and install. Since you've tried and failed asking Plusnet to upgrade the router remotely is perhaps the best solution.
David

[#3]

Thanks Spraxyt, didn't realise it could be done remotely. Will ask nicely. 

[#4]

Hi rogadodge,
I've replied here
Jojo