The aluminum on dibond is probably gonna be something gummier than the usual 6000 series that gets cut on CNCs.
I’ve recently cutout some pieces out of 0.5mm thick 1000 series aluminum, and I’ve found out that it’s thin enough that you can easily cut it in a full dept pass without using an adaptive toolpath.
However, it gums up tools much faster than usual. To avoid it, on a single flute, I was going at 700mm/min.
You are gonna have to figure it out, because different grades machine differently, if I were you I would do at least two passes: one to cut the top aluminum layer and part of the polyethylene, and another for the rest.
However, I’ve never machined PE, and it may require different feed rates. In that case, just do a 0,3mm DOC with aluminum speeds, then dial in your feeds for the plastic layer, and finish with another 0.3 pass.
Also, there is an aluminum guide: https://www.v1engineering.com/aluminum-guide/