50% decrease in Upload Speeds

From February 8, 2025 until March 30, 2025 every speed test performed on multiple devices (3 computers - 2 phones) were consistently returning 355 Mbps for upload speeds regardless of connected via wifi or ethernet cable. Have screen shots to verify this. 

Starting March 30th all tests showed a 50% reduction in upload speeds - now only 177 Mbps. Tested connecting directly to modem via ethernet cable - same result - rebooted modem several times - no change. 

800 Mbps plan - Next Gen Speed Tier Netgear  - CM3000 modem purchased in March 2024 which increased upload speeds from 24 Mbps to 120 Mbps.

Sometime between February 3 and February 8 upload speeds increased from 120 Mbps to 355 Mbps -  Sometime between 3/21 and 3/30 the upload speeds decreased to 177 Mbps.

No changes to hardware/software/account/etc
Download speeds are not an issue - 924 Mbps to 930 Mbps.

Have called Tech Support twice - first time on the 30th and again on the 31st. On the 30th I was told that everything is fine with the connection to my modem but there was planned maint work scheduled for that night - wait until the morning and try again. Did that - rebooted modem on 31st - no change. Called again on 31st and was told everything on the modem looks great - but was told Xfinity had identified an intermittent issue on their network. 

Both times I asked for a ticket to be opened and escalated and was told they could not do that. Could only send a tech out to check line but at no cost - asked if I could get the no cost statement in writing and was told no. No need to come to  my house to check an issue in the Xfinity network. Modem has always shown I have an excellent connection and very low error rates - typically after an MDD error or T3 error. 

5 hours after last modem reboot modem shows zero errors on any channel - 32 down - 4 up - Power 5.0 to 7.2 snr 44.9 to 45.5 Upstream power 38.8 to 40.3 zero uncorrectable code words.