Depends on what you mean by unplug. If you simply mean unplug the power cord, then that is extremely bad advice. In most, if not all cases, the un-powered preamp passes almost NO signal, so it is worse than having no preamp at all.

Please remember that you are in a signal-poor area, and what has worked for you is not generally applicable.

Generally spreaking higher is better, but finding the sweet spot for the desired station(s) often requires tweaking the final height a few inches up, & many times down 6 or so inches from my experiences. I've seen this happen even with strong UHF signals less than 10 miles away.

If you decide to invest in an XG91, I would not take the 8200u down right away. Instead, I would search for a mounting location with a good view of the ESB (WCBS) while shielded from WFSB (perhaps by the structure of your house).

If that proved unsuccessful, try for the opposite, look for WFSB while shielded from the ESB WCBS signal.

In either case, I would not put a preamp or distribution amplifier on the XG91 while it's dedicated to reception of one of the real channel 33 transmissions.

Your location requires some extraordinary effort to get reliable reception of a CBS affiliate. You may find it necessary to have one antenna dedicated to reception of just one or just a few stations, plus the general use antenna.

Of course you can try using the XG91 as a replacement for the 8200u... but the 8200u is up there working well on other channels at this point and the XG91 will not provide CH-2 to 13 coverage either.

Follow up
 

I decided to replace my attic cable run RG-6 with RG-6 Quad that had factory
ends in the closest precut size to my need ( 25'). I am happy to report a major improvment in the quality of all the channels. Even channel 2 is a little better
but it still pixilates freezes and blanks out at random time.

I found that if I aim the antenna toward Connecticut, I am able to get a stable wcbs channel signal. This was not possible during the past 2 weeks.


My next move is to replace the antenna run RG-6 with RG-6 Quad from the preamp on the antenna to the amp /splitter area about 40' feet away.

I'll post my results.

In closing ...I'd like to thank everyone for their suggestions.