I just created an alternative firmware that is compatible with both nRF51 and nRF52 platforms. It's using the Softdevice S130/S132 2.0.0 from Nordic SDK11.

I already tried it on this modules:

• E104-BT5032A board from EBYTE which can be purchased here https://www.aliexpress.com/item/4000538644215.html
• "AliExpress beacon" which can be purchased here https://www.aliexpress.com/item/32826502025.html

More info here:
https://github.com/acalatrava/openhaystack-firmware/tree/main/apps/openhaystack-alternative