Thanks Mike for preparing this light curve comparison. The spectrum has shown interesting changes too over this date range (see attached comparison 2025 Aug 14 v 2026 May 10). The emission line changes have been much discussed. But in agreement with the light curves you have compiled from AAVSO data, the spectrum seems to have reddened significantly. It now diverges signifcantly from the shape of the spectrum of del Vir which I think is considered a template M3III type star, the spectral type of the red giant in the T CrB system. I wonder too what is occurring?
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