Internet drop outs

I have been using my own Arris T25 modem and TP Link AX5400 router for two years.  I was using an XB5 gateway, but after Comcast broke setting up port forwarding in the app and blocking the gateway admin page, I purchased my own stuff.  The setup has worked flawlessly with the exception of this month.  At the beginning of July, while I was out of town, my internet went out.  It reconnected about 20 minutes later.  A storm came through a day or so later and knocked out my power for about 16 hours.  The modem connected back up fine but the router lost all of its settings.  Luckily I had a restore file made and got everything back up in a few minutes.  Since that first outage occurred, my internet has been dropping out once a week, and last week it's happened every other day.  I can unplug and replug the modem and everything comes back up in about 3 minutes, but I shouldn't have to do that.
I received a text message from Xfinity a couple weeks ago (after the power outage) about how they detected a problem with my network and wanted to come fix it.  The technician came out and wasn't aware I received the text, so he wasn't really sure what to do.  He replaced the amplified 8 way splitter I had with a passive 2 way splitter and thought that would help. He also re-terminated the RG6 connectors outside the house and installed a proper ground wire.  
This problem seems to be getting worse as it is happening every other day as I mentioned.  I don't believe the router is failing as all my networks still show when the internet is out.  It just shows an orange light instead of green on the network LED.  The digital phone line still works when the network is out, still I don't think it is the modem either.  I think it' something on Comcast's end.  
Any suggestions of things to look for or further troubleshoot?