Q: iPad4 fail GSM connect after 9.3 update

My iPad 4 always work fine, until upgrade to IOS 9.3 after that i begin to have issues in conect to GSM network, most of times whith no signal or very poor.

I went to network provider (Vodafone Portugal), and they ask me to do a reset to iPad and content with no restore of setings and content, and I did, stll failing, they change the GSM card, and stll failing, already update to 9.3.1 , and to 9.3.2 and still failing.

How can I go back to IOS 9.2?

One momente have network

And next seconds no service

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