SJICube.wcs.pixel_to_world() always returns SkyCoord in the Helioprojective frame at the beginning of the observation

[yjzhu-solar]

The pixel_to_world() method returns SkyCoord defined in the Helioprojective frame when the observation started instead of the Helioprojective frames when individual exposures were made.

irispy_cube = irispy.io.read_files("../../src/IRIS/20221024/1904/iris_l2_20221024_190447_3643101203_SJI_1400_t000.fits")
irispy_cube.wcs.pixel_to_world(182,193,230)

returns

[<SkyCoord (Helioprojective: obstime=2022-10-24T19:04:49.770, rsun=695700.0 km, observer=<HeliographicStonyhurst Coordinate for 'earth'>): (Tx, Ty) in arcsec
     (-415.14377593, 193.85138739)>,
 <Time object: scale='utc' format='isot' value=2022-10-24T19:21:32.420>]

Note that the exposure was made at 2022-10-24T19:21:32.420 but the Helioprojective frame was defined at 2022-10-24T19:04:49.770.

[Cadair]

I am not actually sure there is a way to do this at the moment. We have the same issue with the DKIST WCSes.