We present new spectroscopic and photometric observations of ATLAS18qtd/SN 2018cqj , a fast-declining Type Ia supernova with variable H \alpha emission in previously-published nebular phase spectra .
ATLAS18qtd is undetected in both spectroscopic and photometric observations which occurred at \sim 540 ~ { } d after maximum light and \sim 230 ~ { } d after the last H \alpha detection .
With these new non-detections , we place an upper limit on the H \alpha luminosity of \lesssim 1.1 \times 10 ^ { 36 } ~ { } erg~ { } s ^ { -1 } indicating the H \alpha flux decreased by a factor of \gtrsim 4 since the previous detection .
This upper limit excludes H \alpha emission that plateaus or increases since the previous detection but can not confirm that the H \alpha emission decay rate is equivalent to the supernova decay rate .