See ATEL 15244: https://www.astronomerstelegram.org/?read=15244
"[..] at February 25/26 (MJD = 59636.0) averaged brightness was 16.13 +/- 0.03.
According to published data, we detected the brightest optical state of 3C345 since 2018 May (ATel #11624). Further observations of 3C345 in all ranges are highly encouraged. Resulting photometrical curve in range MJD=59240-59636 is presented on Figure https://drive.google.com/file/d/1OTm1Sum5JAl2LHNgOI-snGznEokRwJc9/view?usp=sharing "
I noticed that there are already recent observations 3C345 in the AAVSO database, but no official sequence for comparison stars, so I requested one.
I would always recommend to use an official sequence rather than your own comparsion stars. Requesting a new sequence is really super easy and in almost all cases (very bright stars can be problem) the sequence will be generated within a very short time, see details here : https://www.aavso.org/request-comparison-stars-variable-star-charts