Anyone else notice speeds drop while set to IP Passthrough?

ASK box seems to be connected to 5G/LTE while in IP Passthrough feeding service to Eero 6+ network. If I reset the box the ASK cube will connect back to 5G UW/C Band and I’ll get ~300 down until I put the ASK box back into IP Passthrough and then it seems stuck on the non C Band speeds again. This whole process is reproducible with the ASK box in different locations. https://i.imgur.com/qkFkZJl.jpg