We had basically yhe same setup. At the end of 250' of chain was 50' of rode. The rode firmly attached in the anchor locker around the windless base. I sprayed red paint at the point where the line whent taught and put a small loop in the line to hook a float on.

If I ever needed to abandon the entire ground tackle on a moments notice the idea was to let everything out, hook the float bottle to the rode just ahead of the red paint and cut the rode. I'm free to leave the anchorage and can come back to my anchor when the time is right.

You never know when getting out ASAP is the primary goal.