This firmware improves the behaviour in card emulation and peer-to-peer (initiator) mode, allowing more reliable exchanges with most smartphones running either in reader or peer-to-peer (target) mode.
The new firmware is here: https://files.springcard.com/firmwares/springprox/1-75/2212_pn512_nfcroll-10_1-75.mot
The firmware upgrade procedure is here: https://tech.springcard.com/firmware-upgrade/csb6-firmware-upgrade/
The new firmware is here: https://files.springcard.com/firmwares/springprox/1-75/uc3b0256_pn512_h512_1-75.hex
The firmware upgrade procedure is here: https://tech.springcard.com/firmware-upgrade/h663-h512-firmware-upgrade/