I have two backups for this situation, the easiest one is to broadcast my mobile internet as WiFi, and so that’s what I’m doing. Most months I don’t use my allocation anyway.
TM sometimes goes down after heavy rain. More often it just becomes even slower than usual. I pay for 8 Mbps, but sometimes get around 1 Mbps, and often even 35 Kbps. In contrast, my mobile connection is 35Mbps consistently. Makes me want to give up TM and pay for more mobile internet allocation.
Meanwhile I’ll restart my router sometimes and maybe TM will come back.