BT vs BTA

"BT" is shorthand for "Best" in the good/better/best licensing scheme: https://www.f5.com/pdf/licensing/good-better-best-licensing-overview.pdf  IIRC the license code becomes "BTA" when extra "Advanced WAF" features are enabled in the license. You can look at your bigip.license file on each big-ip box to know for sure what features are enabled in any specific license.

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