Hello AMPL community and team.
I am not sure if this is possible. But I have a proposal, to deal with the current fairness of the rebase time.

1. Problem:
Currently the rebase time is suboptimal for certain timezones, for example europeans, because the rebase occurs at 4am in the morning. This way its hard for euopeans to position their buy/sells nicely to profit from rebase swing trading.

2. Solution:
Make the rebase time rotating. For example instead of every 24h make it every 24.5 or every 23.5 hours. This way rebase time will be fair for every timezone.

3. Examples:
There is a project called vether which has a similar solution for a timed event.

4. Source:
https://vetherasset.org/whitepaper "Vether is auctioned off in Days of around 23.5 hours. ... The overlapping time periods ensure Day and Era changes happen across different time periods and seasons globally."