Just lost Broadband but lights showed Connected

[#1]

I just lost Broadband on my PC, for 10 -15 minutes or so. Checked the Openreach Modem, all lights OK, solid Green. Unplugged router, then unplugged Phone line connection, and the green connected light stayed on. Rebooted Modem and eventually the Broadband connection returned. Does this suggest line work further upstream on the Fibre Network? I'm not sure that there's anything wrong on my home network, its all running normally.

PlusNet Is there any work being done on my local network (LYMINGE Exchange, Cabinet 2)?

[#2]

Could have just been the router, or modem that locked up, but unless you checked the logs before you rebooted them you won't know.

[#3]

Thanks Mustram.

[#4]

My mother had the green light staying on when unplugged, BT engineer replaced the modem as it was faulty even though it would operate fine
You losing any speeds?

[#5]

@edtsaunders, Speeds are good, very steady. Puzzling isn't it. If the modem is suspect I have an alternative I can use. I'll monitor it for now, see if there really is a problem.