it is likely that apple will carry out the signing of ios 13.1.2 and 13.1.3 in the next few days, then users will not be able to upgrade or downgrade to these two versions.
here are 2 ways to check the sign status of ios firmware that users can choose to use on their ios device.
if you also feel that using ios 11.3 beta is less stable, not suitable for your device, you can choose to downgrade ios 11.3 to bring your device to the previous operating system
after the developer version, ios 10 was released by public beta, which ordinary users can download and install. if you are trying the public beta version, you will experience some
after ios 9.3.5 sign lock of devices using apple a5 chip, apple surprised users when there is a sign opening move for ios 7, ios 8 versions on iphone 5, iphone 5s.