FFmpeg – Multiple overlays at specific times

I have two inputs that are the same image. The first one, I loop to create a video for 8 seconds. I also create two streams that I will overlay. The background is the normal video, and above it is the same video with a LUT (Look-Up Table) that I applied earlier. I make the top video appear as an overlay with a fade-in effect that lasts x seconds before reaching 100%. To create a ‘flash’ effect, I want to overlay instances of my base image (participant1.jpg) at different very close intervals. The first overlay displays, but not this one “[out][1]overlay=enable=”between(t,3.25,3.26)”[outv]”, and I can’t figure out the reason. Have I made a mistake somewhere? Thank you very much for your valuable advice 🙂

ffmpeg -loop 1 -i participant1.jpg -i participant1.jpg -filter_complex "\
[0]split=2[v1][v2];\
[v2]format=rgba,lut3d='red.cube'[v3];\
[v3]fade=in:st=0.25:d=2.93:alpha=1[ov];\
[v1][ov]overlay[bg];\
[bg][1]overlay=enable="between(t,3.20,3.21)"[out];\
[out][1]overlay=enable="between(t,3.25,3.26)"[outv]"\
 -map "[outv]" -c:v libx264 -t 8 -pix_fmt yuv420p output.mp4