Since 2022 I'm running a little website with the schedule of the supercons / Europe events - it feels longer, but this is what I have. But I always wanted to have the schedule on my badge(s) as well and this feels like a reasonable aproach - you can reuse it for multiple events on multiple badges. 

I will try to make it as easy as possible to update the data on the eeprom,  hopefully with an export from my schedule site. https://supercon.davedarko.com/supercon24.php

The PCB is a small adapterboard, I used silkscreen to make it look a bit like a calendar showing the month November of 2024 with the supercon weekend being silver.

Since Aisler has a coupon "AUTUMN24" going (valid till end of year), I've ordered 12 PCBs for 3 Euros and the DS3231 modules were bought on aliexpress through their 3 for 2,99 program and I ended up with 12 modules for 12 Euros.