This star has now faded to around mag 15. Gary prompted me to look at my images since my magnitude estimates of this star were too bright as it faded. One of the problems with automating everything is that I don’t often look at images or the data derived from them and there is a fairly bright star only 7 arcsec to the SW which was within my photometric aperture. The AAVSO VSX does warn about this. Looking in detail at my unbinned images tonight there is also a 15th mag star only 3 arcsec to the NW of the variable and this will generate significant errors at the current level. This is not mentioned anywhere and I haven’t seen it on other images since it is normally swamped by the bright variable. It is in Gaia EDR3 (a demonstration of how good the optics in that spacecraft are). It is worth considering if you are doing photometry of this star at the moment.
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