RBR750 major issues after FW 4.6.3.7

Just wanted to add to this thread I ran into the same issues.  I have an RBR750 with two RBS750 satellites.  I updated to the v4.6.3.7 f/w after being notified by the Orbi app.  Having all sorts of issues ever since.  Spent 3 hours on 4 different support calls, talking to 4 different engineers (one disconnet and no call back as was told would happen if disconnected).  Router and satellites updated fine at first, but within a few hours one of the RBS750 dropped off and would not connect back to the mesh network.  Multiple factory reset attempts prior to support call, and then several more with different engineers did not solve.  Getting a replacement RBS750, paying for the shipping.  Was told since was my first call would get support...even though I had paid for premium h/w support through 6/2022...in any event, the f/w caused the issue...it took effort, but netgear support setup an RMA.  Waiting for shipping confirmation at this point...had to provide proof of purchase (even though bought through netgear.com) and picture of tag with s/n, mac, etc.  Performance is horrible since upgrade...multiple devices have much higher latency, my 1Gb down/25Mb up is performing at ~50% of pre-upgrade.  From ~900Mbps to max so far of 590Mbps.  Afraid to perform any reboot or power cycle for fear it will just stop working...hoping an updated f/w is soon to come to fix these issues...so many reports of other users with Orbi 7xx series with similar issues.  I wish I had searched here before proceeding with upgrade.  If this does not improve soon, I will be switching to a different product...too many issues.